Questions about some-fn and every-pred (possible bug, and improvements)
Hello, I am trying to understand the rationale behind the current implementation of some-fn and every-pred, there seems to be a couple of odd things, or maybe that is just me misunderstanding their doc. user ((every-pred (fn [_]))) true user ((some-fn (fn [_]))) nil Shouldn't the first example return false? since the first function always returns nil? I was also wondering if it would make sense to add a 0 argument version of these, it would make their usage with apply more convenient, and comp which has a smiliar signature behaves like that: user ((comp) true) true user ((some-fn) true) ; Evaluation aborted. user ((every-pred) true) ; Evaluation aborted. Max -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
Max Penet m...@qbits.cc writes: user ((every-pred (fn [_]))) true user ((some-fn (fn [_]))) nil Shouldn't the first example return false? since the first function always returns nil? No. ((every-pred a b c) o1 o2 ...) returns true if all predicates a, b, and c return true for all given args o1, o2, and so one. You don't pass any args, so this is basically (and), which also returns true. `and` is true if all arguments are logically true, which is trivially given when none are provided. I was also wondering if it would make sense to add a 0 argument version of these, it would make their usage with apply more convenient, and comp which has a smiliar signature behaves like that: user ((comp) true) true user ((some-fn) true) ; Evaluation aborted. user ((every-pred) true) ; Evaluation aborted. (comp) is `identity` which makes sense. What would the semantics be for every-pred and some-fn? IMO, it should be user ((some-fn) no-matter-what) false user ((every-pred) no-matter-what) true e.g. (some-cn) was equivalent to (constantly false) and (every-pred) was equivalent to (constantly true). Bye, Tassilo -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
user (every? identity []) true I think I understand now, this might be to match the behavior of every?. Max On Thursday, October 25, 2012 12:31:57 PM UTC+2, Max Penet wrote: Hello, I am trying to understand the rationale behind the current implementation of some-fn and every-pred, there seems to be a couple of odd things, or maybe that is just me misunderstanding their doc. user ((every-pred (fn [_]))) true user ((some-fn (fn [_]))) nil Shouldn't the first example return false? since the first function always returns nil? I was also wondering if it would make sense to add a 0 argument version of these, it would make their usage with apply more convenient, and comp which has a smiliar signature behaves like that: user ((comp) true) true user ((some-fn) true) ; Evaluation aborted. user ((every-pred) true) ; Evaluation aborted. Max -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
On Thursday, October 25, 2012 12:49:32 PM UTC+2, Tassilo Horn wrote: Max Penet m...@qbits.cc writes: user ((every-pred (fn [_]))) true user ((some-fn (fn [_]))) nil Shouldn't the first example return false? since the first function always returns nil? No. ((every-pred a b c) o1 o2 ...) returns true if all predicates a, b, and c return true for all given args o1, o2, and so one. You don't pass any args, so this is basically (and), which also returns true. `and` is true if all arguments are logically true, which is trivially given when none are provided. Ok that makes sense. I was also wondering if it would make sense to add a 0 argument version of these, it would make their usage with apply more convenient, and comp which has a smiliar signature behaves like that: user ((comp) true) true user ((some-fn) true) ; Evaluation aborted. user ((every-pred) true) ; Evaluation aborted. (comp) is `identity` which makes sense. What would the semantics be for every-pred and some-fn? IMO, it should be user ((some-fn) no-matter-what) false user ((every-pred) no-matter-what) true e.g. (some-cn) was equivalent to (constantly false) and (every-pred) was equivalent to (constantly true). Yes I understand that, the proposal was just to avoid exceptions when used with apply, but this could end up be bit confusing maybe, and it can be tested beforehand anyway. Max -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: A Practical Optional Type System for Clojure
Hi Ambrose, great work! I found a typo on page 14, you wrote ... equivalent to [- (U nil String] in Typed Clojure 2012/10/25 Ambrose Bonnaire-Sergeant abonnaireserge...@gmail.com Hi, I have submitted my honours dissertation for marking, for those interested: https://github.com/downloads/frenchy64/papers/paper.pdf Corrections welcome! Thanks, Ambrose -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Disconnect a downstream channel in lamina
I use lamina channels in a library that maintains multiple event streams. The event source is the Asterisk Management Interface, whose raw events are processed, filtered, collated, and finally pushed into appropriate lamina channels. On the client side of my library I want to expose the event streams as a web service. My challenge is to implement long polling: a request either finds events already enqueued, returning immediately; or blocks until an event occurs (with a timeout), then accumulates any further events for a short period, then returns the accumulated events. This reduces network overhead for the typical case of events occuring in short bursts (a single user action triggers several events). I have implemented this behavior in a piece of code that occupies its thread for the entire duration of the request: (require [lamina.core :as m] [lamina.core.graph.node :as node] [lamina.core.channel :as chan]) (let [evs (node/drain (chan/emitter-node ch)) evs (if (seq evs) evs (try (let [ev @(m/with-timeout POLL-TIMEOUT (m/read-channel ch))] (Thread/sleep EVENT-BURST-PERIOD) (conj (node/drain (chan/emitter-node ch)) ev)) (catch TimeoutException _ nil)))] (vec evs)) I would instead like to do this without blocking the thread. Ideally, I'll use aleph to implement the web service and connect a downstream HTTP response channel to my library's lamina channel. What I'm missing is, how do I disconnect the downstream channel without breaking anything in the upstream channel? I want to cleanly disconnect it, let my channel enqueue any further events, then later connect another aleph channel, which will drain those events with no loss. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: A Practical Optional Type System for Clojure
Nice catch! Thanks! On Thu, Oct 25, 2012 at 7:08 PM, Bronsa brobro...@gmail.com wrote: Hi Ambrose, great work! I found a typo on page 14, you wrote ... equivalent to [- (U nil String] in Typed Clojure 2012/10/25 Ambrose Bonnaire-Sergeant abonnaireserge...@gmail.com Hi, I have submitted my honours dissertation for marking, for those interested: https://github.com/downloads/frenchy64/papers/paper.pdf Corrections welcome! Thanks, Ambrose -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
Max Penet m...@qbits.cc writes: Hi Max, user ((some-fn) no-matter-what) false user ((every-pred) no-matter-what) true e.g. (some-cn) was equivalent to (constantly false) and (every-pred) was equivalent to (constantly true). Yes I understand that, the proposal was just to avoid exceptions when used with apply, but this could end up be bit confusing maybe, and it can be tested beforehand anyway. No, I think it's a valid request and it wouldn't be more confusing than (and) = true (or) = false. I'll create a ticket and patch for it. Bye, Tassilo -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Some Friend documentation and regarding documentation in general
I've digested openid and using it with google, should have a working example to share when I have a time to put it together over weekend. I've got another common useage pattern I'd like to ask about: How do we accomplish automatic redirect to the correct page? Let's say user accesses /secret, isn't authenticated and gets redirected to /login by friend. once authenticated, how do we ensure we get redirected back to /secret? On Wednesday, October 24, 2012 10:12:01 AM UTC+1, Patrik Sundberg wrote: On Wednesday, October 24, 2012 3:10:52 AM UTC+1, David Della Costa wrote: Patrik, Pierre, have you folks checked out the mock app that Chas created in the test directory? It's not going to give you everything you're looking for but make it can help. There is an implementation of the OpenID workflow in there, including a credential-fn example: https://github.com/cemerick/friend/blob/master/test/test_friend/mock_app.clj Been digesting that and reading the OpenID workflow + the openid2java docs to work out what inputs mean what. I'm not quite there yet but starting to have some idea, will experiment today to get auth with Google Account up and running. This may also help, regarding credential functions: https://github.com/cemerick/friend/blob/master/test/test_friend/credentials.clj I also highly recommend looking at the bcrypt-credential-fn in the credentials.clj lib, in the src of the project itself: https://github.com/cemerick/friend/blob/master/src/cemerick/friend/credentials.clj The credentials I grok more easily than the workflow - or more specifically the openid workflow. The form based auth workflow is a lot easier for me to follow, no probs there. That I find the openid workflow more obtuse probably means I don't get OpenID quite yet so will do some standard reading there as well. This is the default credentials function used in the mock app above, so it should help illustrate some of the concepts. I've spent a lot of time poring over the code too, so feel free to ping me with questions too, I may be able to help. IMHO the doc is really lacking and I have to say I was expecting more guidance in the code itself. Yes, it's still hard to wrap your head around the docs. Friend scratches an itch I have, and I think it's going to be rather important if people are trying to web apps quickly in Clojure, so I'm going to keep working on it and see how much I can clean things up and make concepts more clear. And I know Chas is interested in this as well, from his past comments. Any help and pull requests are welcome. ;-) I'm working on some updates to everything I've been working on, I'll post updates to the list shortly (later this week probably, maybe even today). Agreed. Happy to contribute a working google acc openid auth once I get there. Patrik DD 2012/10/24 Pierre R p.rade...@gmail.com: Thanks David for the extra doc. I have had a try with OpenID. Everything works kind of expected. I had a question about 302 redirection prior to authentication that I posted on github. Another question is how to link the concept of roles with the openid credentials. IMHO the doc is really lacking and I have to say I was expecting more guidance in the code itself. I guess a lot of stuff obvious to an experienced clojure developers are still dark magic to me. In particular it is rather difficult to understand how to write a crendential-fn and this link won't help you ;-) https://github.com/cemerick/friend/blob/master/docs/credentials.md For OpenId I have blindly used the identity function without much understanding ... I am using Friend to scratch a little auth server. Not sure it is the best fit for that purpose. I will see. I hope Friend is going to be reviewed by an extended community of people much more qualified than myself to talk about such matter. Still docs could be improved and I believe helps could come from pull requests to suggest the addition of code comments there and there. If I dig far enough in the code, I would be pleased to help. Thanks for the hard work. Cheers, Le mardi 23 octobre 2012 17:50:25 UTC+2, Patrik Sundberg a écrit : These are great tutorials. Thanks for publishing. Right now I'm looking for something similar using the OpenID workflow. I see it's there but how I use to for example create a sign in with google setup is less clear to me. Has anyone got a good OpenID example out there somewhere? On Saturday, October 6, 2012 4:50:05 PM UTC+1, David Della Costa wrote: Hi folks, I've been pretty slack in communicating via the mailing list, but I realized today that there is a lot of important dialogue going on here so I have to make more of an effort to take part--I want to be a part of this community!
Re: Rouge: Ruby + Clojure
Hi all, As a final (!?) follow-up to this post, you can now play with Rouge online in a tryclj-like environment: http://try.rouge.io Cheers, Arlen -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
Tassilo Horn t...@gnu.org writes: user ((some-fn) no-matter-what) false user ((every-pred) no-matter-what) true e.g. (some-cn) was equivalent to (constantly false) and (every-pred) was equivalent to (constantly true). Yes I understand that, the proposal was just to avoid exceptions when used with apply, but this could end up be bit confusing maybe, and it can be tested beforehand anyway. No, I think it's a valid request and it wouldn't be more confusing than (and) = true (or) = false. I'll create a ticket and patch for it. Done, see http://dev.clojure.org/jira/browse/CLJ-1094 In contrast to what's written above, I decided to make (some-fn) to be (constantly nil), which matches the behavior of `some` better than (constantly false). Bye, Tassilo -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Questions about some-fn and every-pred (possible bug, and improvements)
Thanks, perfect, I had prepared a patch that was identical. On Thursday, October 25, 2012 2:11:44 PM UTC+2, Tassilo Horn wrote: Tassilo Horn ts...@gnu.org javascript: writes: user ((some-fn) no-matter-what) false user ((every-pred) no-matter-what) true e.g. (some-cn) was equivalent to (constantly false) and (every-pred) was equivalent to (constantly true). Yes I understand that, the proposal was just to avoid exceptions when used with apply, but this could end up be bit confusing maybe, and it can be tested beforehand anyway. No, I think it's a valid request and it wouldn't be more confusing than (and) = true (or) = false. I'll create a ticket and patch for it. Done, see http://dev.clojure.org/jira/browse/CLJ-1094 In contrast to what's written above, I decided to make (some-fn) to be (constantly nil), which matches the behavior of `some` better than (constantly false). Bye, Tassilo -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: future with user specified ExecutorService
wrong commit: https://github.com/mpenet/clojure/commit/9c6e47524dc21c6bdfaa9d0cc2a69377cc69cbf3 On Thursday, October 25, 2012 2:35:01 PM UTC+2, Max Penet wrote: Another enhancement proposal, would it be possible to have a future-call arity with an additional argument as the ExecutorService used. It seems to be a trivial but useful modification, but I wanted to ask here before creating a ticket for this. Something like this maybe: https://github.com/mpenet/clojure/commit/e5295ac1aa49036c98a3a4e18cba974cd72483d5 Max -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
ANN: inet.data 0.5.1
Hi: Inet.data is a Clojure library for modeling various Internet-related conceptual entities as data. It is intended to support applications which are *about* the modeled entities versus *interfacing* with them. It presently contains types and associated APIs for representing IP addresses, IP networks, and DNS domains. None of the provided functions will ever perform any sort of DNS resolution or other network operation on the entity represented. Instead, it supports such operations as network address enumeration, network and DNS zone set membership tests, and domain suffix list lookups. Overview documentation and source code available at: https://github.com/llasram/inet.data Detailed API documentation at: http://llasram.github.com/inet.data/ Leiningen dependency coordinates: [inet.data 0.5.1] Feedback and contributions welcome! -Marshall -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
Hmm, how do I include this? I have a strange error. I had an app that was working fine, and then I added this one line at the the :require block in core.clj: (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json] [clojure.java.io]) I added that last line, and now, when I compile, I get: Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: This makes no sense to me, since the JSON was working fine the last time I compiled. On Wednesday, October 24, 2012 11:11:11 PM UTC-4, yangsx wrote: clojure.java.io/file On Thu, Oct 25, 2012 at 11:08 AM, larry google groups lawrenc...@gmail.com javascript: wrote: I want to use clojure.contrib.java-utils/file. I am using Clojure 1.3 and leinengen. What is the modern equivalent of clojure.contrib.java-utils/file? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.comjavascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Some Friend documentation and regarding documentation in general
On Oct 25, 2012, at 8:04 AM, Patrik Sundberg wrote: I've digested openid and using it with google, should have a working example to share when I have a time to put it together over weekend. I've got another common useage pattern I'd like to ask about: How do we accomplish automatic redirect to the correct page? Let's say user accesses /secret, isn't authenticated and gets redirected to /login by friend. once authenticated, how do we ensure we get redirected back to /secret? I think that's a bug in the OpenID workflow. Friend will do this redirection automatically if the workflow enables it: https://github.com/cemerick/friend/blob/master/src/cemerick/friend/workflows.clj#L79 There are a couple of testcases in the project that verify this; unfortunately, the OpenID workflow doesn't yet accept the same configuration option as the interactive form workflow. Please file an issue, and, if you are so bold, a patch. :-) Thanks, - Chas -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
what is the simplest user auth system possible?
I have a website written in PHP, using the Symfony framework, which is a monolithic framework much like what Ruby On Rails used to be. I have been slowly re-writing the website in Clojure, and as I do this I've been breaking up the system into several small apps, rather than one huge monolithic app. For my next step, I need to come up with a user system. My needs are minimal: I only need to know when someone is logged in, and I need to associate them with some user id (the id will simply be the id from a user table kept in MySql). I am curious what is the absolutely easiest way to do this? I think Ring has functions for sessions, so I could perhaps compose this app with Ring, Jetty, Moustache and Korma? I have almost no experience with Ring, but is it able to handle the sessions? Is there any jar that offers a standard way of handling username and passwords in Clojure, or should I write that code myself? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Some Friend documentation and regarding documentation in general
On Thursday, October 25, 2012 1:59:36 PM UTC+1, Chas Emerick wrote: On Oct 25, 2012, at 8:04 AM, Patrik Sundberg wrote: I've digested openid and using it with google, should have a working example to share when I have a time to put it together over weekend. I've got another common useage pattern I'd like to ask about: How do we accomplish automatic redirect to the correct page? Let's say user accesses /secret, isn't authenticated and gets redirected to /login by friend. once authenticated, how do we ensure we get redirected back to /secret? I think that's a bug in the OpenID workflow. Friend will do this redirection automatically if the workflow enables it: https://github.com/cemerick/friend/blob/master/src/cemerick/friend/workflows.clj#L79 There are a couple of testcases in the project that verify this; unfortunately, the OpenID workflow doesn't yet accept the same configuration option as the interactive form workflow. Please file an issue, and, if you are so bold, a patch. :-) Got it, adding it to my weekend list. Thanks! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the simplest user auth system possible?
On Oct 25, 2012 9:04 AM, larry google groups lawrencecloj...@gmail.com wrote: For my next step, I need to come up with a user system. My needs are minimal: I only need to know when someone is logged in, and I need to associate them with some user id (the id will simply be the id from a user table kept in MySql). I am curious what is the absolutely easiest way to do this? The easiest auth system to write is the one that's already written. https://github.com/cemerick/friend -- Stephen Compall If anyone in the MSA is online, you should watch this flythrough. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: data.json 0.2.0
I am not opposed to having a shim to support an API compatible with older releases. It's not even particularly difficult: https://gist.github.com/3950124 I certainly did not anticipate this release causing significant problems for application or library developers, and if it did then I apologize. However, I will stand by the decision to update the API. data.json 0.1.x suffered from what I consider, in retrospect, to be poor design decisions. Those were decisions I made over two years ago in a hasty effort to please too many people who had conflicting goals: - Converting field names to keywords by default can create invalid keywords. - Keywordization is controlled by a bare boolean argument with little indication of its function. - Inconsistent styles of optional arguments: read-json and write-json take booleans as bare arguments, json-str and print-json use keyword-value pairs. - Parsing a string and parsing from a stream -- two very different operations -- are conflated in a single function. - Functions are not consistently named: json-str, read-json, write-json - Function names repeat the name of the library, rather than using namespaces. It was impossible to solve some of these problems without introducing breaking changes. Looking at the Clojure Library Coding Standards[1], data.json 0.2.0 does a better job at Use good names and Unroll optional named arguments. It fails at Java's commitment to not break existing code. In this instance, I believe the tradeoff is worthwhile because the new API can be more easily extended with additional arguments. This also opened up a place to add new features such as customizable conversion functions, the most-commonly-requested feature for this library. Per Rich's directive[2], I cannot yet make a 1.0.0 release. Therefore, 0.1.3 to 0.2.0 is the largest version bump I can make and the best indication I can give of breaking changes. I hope that these improvements to the API bring this library closer to a 1.0.0-ready state. I'm not trying to make anyone's life more difficult, just trying to provide useful tools. -S [1]: http://dev.clojure.org/display/design/Library+Coding+Standards [2]: http://dev.clojure.org/display/design/Contrib+1.0.0+Releases -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
it looks like clojure.java.io occurs twice, is that why that happens? On Thu, Oct 25, 2012 at 2:58 PM, larry google groups lawrencecloj...@gmail.com wrote: Hmm, how do I include this? I have a strange error. I had an app that was working fine, and then I added this one line at the the :require block in core.clj: (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json] [clojure.java.io]) I added that last line, and now, when I compile, I get: Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: This makes no sense to me, since the JSON was working fine the last time I compiled. On Wednesday, October 24, 2012 11:11:11 PM UTC-4, yangsx wrote: clojure.java.io/file On Thu, Oct 25, 2012 at 11:08 AM, larry google groups lawrenc...@gmail.com wrote: I want to use clojure.contrib.java-utils/**file. I am using Clojure 1.3 and leinengen. What is the modern equivalent of clojure.contrib.java-utils/ **file? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@**googlegroups.com For more options, visit this group at http://groups.google.com/**group/clojure?hl=enhttp://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- I may be wrong or incomplete. Please express any corrections / additions, they are encouraged and appreciated. At least one entity is bound to be transformed if you do ;) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
are you aot compiling? If yes delete all the calss files and re-compile...also there is no reason to require it unless you alias it to something... a common one would be (:require [clojure.java.io :as io])...personally, for clojure.java.io, I just use the fully qualified name most of the times Jim On 25/10/12 13:58, larry google groups wrote: Hmm, how do I include this? I have a strange error. I had an app that was working fine, and then I added this one line at the the :require block in core.clj: (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json] [clojure.java.io]) I added that last line, and now, when I compile, I get: Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: This makes no sense to me, since the JSON was working fine the last time I compiled. On Wednesday, October 24, 2012 11:11:11 PM UTC-4, yangsx wrote: clojure.java.io/file http://clojure.java.io/file On Thu, Oct 25, 2012 at 11:08 AM, larry google groups lawrenc...@gmail.com javascript: wrote: I want to use clojure.contrib.java-utils/file. I am using Clojure 1.3 and leinengen. What is the modern equivalent of clojure.contrib.java-utils/file? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.com javascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
thinking in data, polymorphism, etc.
I'm trying to understand the programming philosophy expressed in some of the videos, as it relates to dealing with data with different representations. There's a lot of emphasis on working with basic collection types, not using getters and setters, and so-forth. I have a fairly common scenario where I have a set of operations that need to work on two types of data (not data types in the clojure sense) that have different internal structure (i.e. maps with different keys). I could write a generic function that operates on both types of map. That would require implementing getters for each type (not sure where those would live). Alternatively, I could use a type-based dispatch, which means converting to records. Does that mean I'm in my defrecord phase, as Stuart put it in the video? Or perhaps I could stick with maps and use a multimethod for dispatch? But dispatch by type and dispatch with multimethod both involve implementing all the algorithms twice, unless the methods I'm dispatching to are just getters (in which case I can write a generic algorithm that uses the getters). I don't think I understand the alternative to getters or the defrecord phase. Have I missed something by arriving at this point in the first place (i.e. thinking I need polymorphic functions)? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On 25/10/12 16:59, Brian Craft wrote: I have a fairly common scenario where I have a set of operations that need to work on two types of data (not data types in the clojure sense) that have different internal structure (i.e. maps with different keys). I could write a generic function that operates on both types of map. I'm not sure I follow why you need polymorphic behavior of any form...the operations that need to operate on 2 internally different maps can take the keys to 'touch' as parameters couldn't they? Then it is truly generic...if this is not practical you can always make a HOF that returns the appropriate handler for the data-type you're examining at any given time...meta-data could help you distinguish between the maps... am I missing something? Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: data.json 0.2.0
On Thu, Oct 25, 2012 at 8:08 AM, Stuart Sierra the.stuart.sie...@gmail.com wrote: I certainly did not anticipate this release causing significant problems for application or library developers, and if it did then I apologize. The biggest problem is transitive dependency conflicts (as I had with congomongo) because this is a very low-level library that is fairly widely used. I agree with nearly all of your reasons for updating the API but maintaining the former API as deprecated would have allowed both application developers and other library maintainers to move at their own pace instead of forcing lockstep upgrades on whole chains of libraries. Deprecated in 0.2.0 and removed in 0.3.0 might have been more appropriate. However, I will stand by the decision to update the API. data.json 0.1.x suffered from what I consider, in retrospect, to be poor design decisions. Agreed. - Converting field names to keywords by default can create invalid keywords. This was the change that caused me the most work since I needed to update all call sites in different ways depending on what the code needed - and then spend a bunch of time carefully testing that I had restored the correct behavior. Yes, the previous behavior could be problematic but switching the default behavior of an API is very disruptive. Since this wasn't mentioned in your highlights, nor in your Change Log, the first I knew of it was when a huge number of my unit tests failed in mysterious ways :( - Keywordization is controlled by a bare boolean argument with little indication of its function. Agreed this was ugly. Having now restored my code's correct functionality, I like the flexibility of the :key-fn approach. - Inconsistent styles of optional arguments: read-json and write-json take booleans as bare arguments, json-str and print-json use keyword-value pairs. Agreed. - Parsing a string and parsing from a stream -- two very different operations -- are conflated in a single function. Agreed. - Functions are not consistently named: json-str, read-json, write-json Agreed. - Function names repeat the name of the library, rather than using namespaces. Agreed. -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
[OT] Khan Academy's computer science platform and Bret Victor's response
Bret Victor has been mentioned before on this list, here's another interesting article he wrote: http://worrydream.com/LearnableProgramming/ Here's a trick question: How do we get people to understand programming? Khan Academy recently launched an online environment for learning to program. It offers a set of tutorials based on the JavaScript and Processing languages, and features a live coding environment, where the program's output updates as the programmer types. Because my work was cited as an inspiration for the Khan system, I felt I should respond with two thoughts about learning Bret responds to John Resig's blog post Redefining the Introduction to Computer Science http://ejohn.org/blog/introducing-khan-cs/ Enjoy, Raju -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: A Practical Optional Type System for Clojure
super cool!!! apparently Racket just had another paper along those lines, won at OOPSLA: http://www.ccs.neu.edu/racket/pubs/oopsla12-tsdthf.pdf more about how to promote from dynamic to statically typed stuff. wadler had some talk about that before, about having a firewall of sorts, i think. hope this kind of stuff also some day gets over to erlang/lfe. :-) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
I have a fairly common scenario where I have a set of operations that need to work on two types of data (not data types in the clojure sense) that have different internal structure (i.e. maps with different keys). Could you please be a little more concrete? If you provide a specific example, we can provide some specific solutions accompanied by some rationale to help you solve similar problems in the future. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 8:59 AM, Brian Craft craft.br...@gmail.com wrote: I have a fairly common scenario where I have a set of operations that need to work on two types of data (not data types in the clojure sense) that have different internal structure (i.e. maps with different keys). I could write a generic function that operates on both types of map. That would require implementing getters for each type (not sure where those would live). Jim touched on this - you could have functions that map the two different input data structures to a common form that the function needs (assuming the call sites know which structure is which). But as Brandon said, if you can give a more specific example...? -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath
I asked this previously but I thought I would start a new thread to go into more detail. This is driving me crazy. I was using json in my app and everything was working great. Then I did something, but I don't know what. Now it is broken. My project.clj is: (defproject who-is-logged-in 1.1 :description When users arrive :dependencies [ [org.clojure/clojure 1.3.0] [net.cgrand/moustache 1.1.0] [ring 1.1.5] [ring/ring-jetty-adapter 1.1.5] ] :main who-is-logged-in.core :jvm-opts [-Xmx1000m]) and the top of core.clj looks like this: (ns who-is-logged-in.core (:gen-class) (:import (java.util Date) (java.io File)) (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json]) (:use [net.cgrand.moustache :only [app delegate]] [ring.util.response] [ring.middleware.params] [ring.adapter.jetty :only [run-jetty]])) I run lein deps and then lein compile. I get this error: Exception in thread main java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: , compiling:(core.clj:1) at clojure.lang.Compiler$InvokeExpr.eval(Compiler.java:3342) at clojure.lang.Compiler.compile1(Compiler.java:6985) at clojure.lang.Compiler.compile1(Compiler.java:6975) at clojure.lang.Compiler.compile(Compiler.java:7046) at clojure.lang.RT.compile(RT.java:385) at clojure.lang.RT.load(RT.java:425) at clojure.lang.RT.load(RT.java:398) at clojure.core$load$fn__4610.invoke(core.clj:5386) at clojure.core$load.doInvoke(core.clj:5385) at clojure.lang.RestFn.invoke(RestFn.java:408) at clojure.core$load_one.invoke(core.clj:5200) at clojure.core$compile$fn__4615.invoke(core.clj:5397) at clojure.core$compile.invoke(core.clj:5396) at user$eval27.invoke(NO_SOURCE_FILE:1) at clojure.lang.Compiler.eval(Compiler.java:6465) at clojure.lang.Compiler.eval(Compiler.java:6455) at clojure.lang.Compiler.eval(Compiler.java:6431) at clojure.core$eval.invoke(core.clj:2795) at clojure.main$eval_opt.invoke(main.clj:296) at clojure.main$initialize.invoke(main.clj:315) at clojure.main$null_opt.invoke(main.clj:348) at clojure.main$main.doInvoke(main.clj:426) at clojure.lang.RestFn.invoke(RestFn.java:421) at clojure.lang.Var.invoke(Var.java:405) at clojure.lang.AFn.applyToHelper(AFn.java:163) at clojure.lang.Var.applyTo(Var.java:518) at clojure.main.main(main.java:37) Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: Like I said, this was working, and now it is broken. Can anyone guess why? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: [ANN] nrepl.el 0.1.5 released
On Mon, Oct 22, 2012 at 5:35 PM, Erlis Vidal er...@erlisvidal.com wrote: Quick question, After follow the installation instructions it looks like version 0.1.4 was installed instead version 0.1.5 do you know why ? Hi Erlis, My guess is you have an old version lying around? Did you install from marmalade? What versions of nrepl.el do you have in your ~/.emacs.d/elpa folder? Cheers, Tim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath
On 25/10/12 18:01, larry google groups wrote: (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json]) I don't like this line... try: (:require [clojure.string :as st] [clojure.java.io :as io] [clojure.data.json :as json] [who-is-logged-in.memory_display :as who]) ;;assuming this is an ns you can reach also try deleting all your class files and recompile...keep your eye on the mailing list cos I think something changed with data.json...there is a discussion currently going on... Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath
To clean do $ lein clean Sent from phone. Please excuse brevity. On Oct 25, 2012 10:36 PM, Jim foo.bar jimpil1...@gmail.com wrote: On 25/10/12 18:01, larry google groups wrote: (:require clojure.string clojure.java.io who-is-logged-in.memory_** display [clojure.data.json :as json]) I don't like this line... try: (:require [clojure.string :as st] [clojure.java.io :as io] [clojure.data.json :as json] [who-is-logged-in.memory_**display :as who]) ;;assuming this is an ns you can reach also try deleting all your class files and recompile...keep your eye on the mailing list cos I think something changed with data.json...there is a discussion currently going on... Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscribe@**googlegroups.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/**group/clojure?hl=enhttp://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: [ANN] nrepl.el 0.1.5 released
Thanks everyone for all the positive feedback. Glad to hear the community is finding this useful. Cheers, Tim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath
Why don't you have clojure.data.json in your dependencies in project.clj? That seems like a problem to me. Dave On Thu, Oct 25, 2012 at 10:01 AM, larry google groups lawrencecloj...@gmail.com wrote: I asked this previously but I thought I would start a new thread to go into more detail. This is driving me crazy. I was using json in my app and everything was working great. Then I did something, but I don't know what. Now it is broken. My project.clj is: (defproject who-is-logged-in 1.1 :description When users arrive :dependencies [ [org.clojure/clojure 1.3.0] [net.cgrand/moustache 1.1.0] [ring 1.1.5] [ring/ring-jetty-adapter 1.1.5] ] :main who-is-logged-in.core :jvm-opts [-Xmx1000m]) and the top of core.clj looks like this: (ns who-is-logged-in.core (:gen-class) (:import (java.util Date) (java.io File)) (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json]) (:use [net.cgrand.moustache :only [app delegate]] [ring.util.response] [ring.middleware.params] [ring.adapter.jetty :only [run-jetty]])) I run lein deps and then lein compile. I get this error: Exception in thread main java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: , compiling:(core.clj:1) at clojure.lang.Compiler$InvokeExpr.eval(Compiler.java:3342) at clojure.lang.Compiler.compile1(Compiler.java:6985) at clojure.lang.Compiler.compile1(Compiler.java:6975) at clojure.lang.Compiler.compile(Compiler.java:7046) at clojure.lang.RT.compile(RT.java:385) at clojure.lang.RT.load(RT.java:425) at clojure.lang.RT.load(RT.java:398) at clojure.core$load$fn__4610.invoke(core.clj:5386) at clojure.core$load.doInvoke(core.clj:5385) at clojure.lang.RestFn.invoke(RestFn.java:408) at clojure.core$load_one.invoke(core.clj:5200) at clojure.core$compile$fn__4615.invoke(core.clj:5397) at clojure.core$compile.invoke(core.clj:5396) at user$eval27.invoke(NO_SOURCE_FILE:1) at clojure.lang.Compiler.eval(Compiler.java:6465) at clojure.lang.Compiler.eval(Compiler.java:6455) at clojure.lang.Compiler.eval(Compiler.java:6431) at clojure.core$eval.invoke(core.clj:2795) at clojure.main$eval_opt.invoke(main.clj:296) at clojure.main$initialize.invoke(main.clj:315) at clojure.main$null_opt.invoke(main.clj:348) at clojure.main$main.doInvoke(main.clj:426) at clojure.lang.RestFn.invoke(RestFn.java:421) at clojure.lang.Var.invoke(Var.java:405) at clojure.lang.AFn.applyToHelper(AFn.java:163) at clojure.lang.Var.applyTo(Var.java:518) at clojure.main.main(main.java:37) Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: Like I said, this was working, and now it is broken. Can anyone guess why? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thursday, October 25, 2012 9:16:58 AM UTC-7, Jim foo.bar wrote:
On 25/10/12 16:59, Brian Craft wrote:
I have a fairly common scenario where I have a set of operations that
need to work on two types of data (not data types in the clojure
sense) that have different internal structure (i.e. maps with
different keys). I could write a generic function that operates on
both types of map.
I'm not sure I follow why you need polymorphic behavior of any
form...the operations that need to operate on 2 internally different
maps can take the keys to 'touch' as parameters couldn't they? Then it
is truly generic...if this is not practical you can always make a HOF
that returns the appropriate handler for the data-type you're examining
at any given time...meta-data could help you distinguish between the
maps...
Is this reimplementing a small bit of what multimethods do? I manually
write something to keep track of handlers, examine the data type of
parameters, and then dispatch? How is that different than a multimethod?
Hm... I'm trying to get more specific w/o getting lost in details. Briefly,
I'm drawing a graphic. The graphic can have different kinds of objects
which define the x axis. In one form, it's a list of objects each of which
includes a numeric range of sub-elements. E.g. [{:name 'A :start 1 :end 10}
{:name 'B :start 1 :end 30} {:name 'C :start 200 :end 400}]. In another
form it's a list of objects each of which includes a list of objects, e.g.
[{:name 'A :elements ['a 'b 'c]} {:name 'B :elements ['d 'e 'f]}].
On mouse events, corresponding elements on the x axis have to be found, but
the way you do this is different for the two types. A drag-zoom handler
might look something like this:
(def drag-zoom [xaxis x1 x2]
(set-position (interval xaxis (find-element xaxis x1) (find-element
xaxis x2
where find-element finds the element at the given coord (e.g. 'A 'b in one
mode, or 'A 8 in the other), interval returns an sub-interval on the xaxis
(like [{:name 'A :elements ['b 'c]} {:name 'B :elements ['d 'e]}], or
[{:name 'A :start 8 :end 10} {:name 'B :start 1 :end 10}], and set-position
updates the current position with the sub-interval.
But, in general, I think any classic OOP example would do. You have 12
types of shapes and a method total-area that finds the sum of the areas of
all the instantiated shapes. If you use maps to represent the shapes, where
do you implement the area calculations for the 12 types of shapes? A
multimethod that inspects a :shape key? Or convert to records? I could do
it javascript functional style and write a function that returns a dispatch
function representing a particular shape, and which implements an 'area'
method. But that's getting very OOP, and I doubt it's idiomatic clojure.
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Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 11:03 AM, Brian Craft craft.br...@gmail.com wrote: that's getting very OOP, and I doubt it's idiomatic clojure. http://www.ibm.com/developerworks/library/j-clojure-protocols/ ? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thursday, October 25, 2012 11:07:23 AM UTC-7, raould wrote: On Thu, Oct 25, 2012 at 11:03 AM, Brian Craft craft...@gmail.comjavascript: wrote: that's getting very OOP, and I doubt it's idiomatic clojure. http://www.ibm.com/developerworks/library/j-clojure-protocols/ ? Hm, yeah, I don't really get protocols, yet. They seem to be all about java classes. If I'm using a map to represent some type of data, would I start putting protocols on maps? Seems like that wouldn't be a good approach, since different protocols would collide. E.g. two shapes represented by maps are going to dispatch to the same area protocol, I think, since they're both maps. I'm not sure. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath
Why don't you have clojure.data.json in your dependencies in project.clj? That seems like a problem to me. Ah, hell. Looks like I accidentally erased that line. Thanks for pointing that out. svn diff -r r3166:3250 project.clj Index: project.clj === --- project.clj(revision 3166) +++ project.clj(revision 3250) @@ -1,8 +1,9 @@ -(defproject who-is-logged-in 1.0.1 +(defproject who-is-logged-in 1.1 :dependencies [[org.clojure/clojure 1.3.0] [net.cgrand/moustache 1.1.0] [ring 1.1.5] - [ring/ring-jetty-adapter 1.1.5]] + [ring/ring-jetty-adapter 1.1.5] + [org.clojure/data.json 0.2.0]] :main who-is-logged-in.core - :jvm-opts [-Xmx4000m]) \ No newline at end of file + :jvm-opts [-Xmx1000m]) \ No newline at end of file On Thursday, October 25, 2012 1:01:54 PM UTC-4, larry google groups wrote: I asked this previously but I thought I would start a new thread to go into more detail. This is driving me crazy. I was using json in my app and everything was working great. Then I did something, but I don't know what. Now it is broken. My project.clj is: (defproject who-is-logged-in 1.1 :description When users arrive :dependencies [ [org.clojure/clojure 1.3.0] [net.cgrand/moustache 1.1.0] [ring 1.1.5] [ring/ring-jetty-adapter 1.1.5] ] :main who-is-logged-in.core :jvm-opts [-Xmx1000m]) and the top of core.clj looks like this: (ns who-is-logged-in.core (:gen-class) (:import (java.util Date) (java.io File)) (:require clojure.string clojure.java.io who-is-logged-in.memory_display [clojure.data.json :as json]) (:use [net.cgrand.moustache :only [app delegate]] [ring.util.response] [ring.middleware.params] [ring.adapter.jetty :only [run-jetty]])) I run lein deps and then lein compile. I get this error: Exception in thread main java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: , compiling:(core.clj:1) at clojure.lang.Compiler$InvokeExpr.eval(Compiler.java:3342) at clojure.lang.Compiler.compile1(Compiler.java:6985) at clojure.lang.Compiler.compile1(Compiler.java:6975) at clojure.lang.Compiler.compile(Compiler.java:7046) at clojure.lang.RT.compile(RT.java:385) at clojure.lang.RT.load(RT.java:425) at clojure.lang.RT.load(RT.java:398) at clojure.core$load$fn__4610.invoke(core.clj:5386) at clojure.core$load.doInvoke(core.clj:5385) at clojure.lang.RestFn.invoke(RestFn.java:408) at clojure.core$load_one.invoke(core.clj:5200) at clojure.core$compile$fn__4615.invoke(core.clj:5397) at clojure.core$compile.invoke(core.clj:5396) at user$eval27.invoke(NO_SOURCE_FILE:1) at clojure.lang.Compiler.eval(Compiler.java:6465) at clojure.lang.Compiler.eval(Compiler.java:6455) at clojure.lang.Compiler.eval(Compiler.java:6431) at clojure.core$eval.invoke(core.clj:2795) at clojure.main$eval_opt.invoke(main.clj:296) at clojure.main$initialize.invoke(main.clj:315) at clojure.main$null_opt.invoke(main.clj:348) at clojure.main$main.doInvoke(main.clj:426) at clojure.lang.RestFn.invoke(RestFn.java:421) at clojure.lang.Var.invoke(Var.java:405) at clojure.lang.AFn.applyToHelper(AFn.java:163) at clojure.lang.Var.applyTo(Var.java:518) at clojure.main.main(main.java:37) Caused by: java.io.FileNotFoundException: Could not locate clojure/data/json__init.class or clojure/data/json.clj on classpath: Like I said, this was working, and now it is broken. Can anyone guess why? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 11:17 AM, Brian Craft craft.br...@gmail.com wrote: http://www.ibm.com/developerworks/library/j-clojure-protocols/ since different protocols would collide. E.g. two shapes represented by maps are going to dispatch to the same area protocol, I think, since they're both maps. i suspect it shouldn't be a problem, since i thought protocols are to support specialization of function per (single dispatchy) type? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 11:17 AM, Brian Craft craft.br...@gmail.com wrote: http://www.ibm.com/developerworks/library/j-clojure-protocols/ Hm, yeah, I don't really get protocols, yet. They seem to be all about java classes. If I'm using a map to represent some type of data, would I start putting protocols on maps? not to be at all snarky, did you read the article? when i read it, it seemed to explain things such that it answers such questions. sincerely. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
clojure.java.io/file http://clojure.java.io/file So, in project.clj, I do this: [org.clojure/io] ? Is there a version number I should put in there? On Wednesday, October 24, 2012 11:11:11 PM UTC-4, yangsx wrote: clojure.java.io/file On Thu, Oct 25, 2012 at 11:08 AM, larry google groups lawrenc...@gmail.com javascript: wrote: I want to use clojure.contrib.java-utils/file. I am using Clojure 1.3 and leinengen. What is the modern equivalent of clojure.contrib.java-utils/file? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clo...@googlegroups.comjavascript: Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+u...@googlegroups.com javascript: For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On 25/10/12 19:20, Raoul Duke wrote: On Thu, Oct 25, 2012 at 11:17 AM, Brian Craft craft.br...@gmail.com wrote: http://www.ibm.com/developerworks/library/j-clojure-protocols/ since different protocols would collide. E.g. two shapes represented by maps are going to dispatch to the same area protocol, I think, since they're both maps. i suspect it shouldn't be a problem, since i thought protocols are to support specialization of function per (single dispatchy) type? Protocols go hand-in-hand with records in order to provide the fastest polymorphic behaviour possible which is no other that type-based dispatch...I still don't understand why you 'd want that from what you've described so far... Going back to your graphics example, I think I've had similar situation in one of my GUIs...I had a canva-react fn that worked for the game of chess but not for any other games. So yes, I made it a multi-method and now consumers of the lib that are supposed to build board-games with i,t can simply add their own canva-react that handles their game...Does this sound similar to what you're trying to do? Jim ps: if you go down the protocol road most likely you'll have to change your maps to records. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On 25/10/12 19:25, larry google groups wrote: So, in project.clj, I do this: [org.clojure/io] ? No no this namespace is part of Clojure itself. No need to put it in the project.clj. Just require it in your namespace where you want to use it... Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
ANN Langohr 1.0.0-beta10 is released
Langohr is a Clojure RabbitMQ client (http://clojurerabbitmq.info) that embraces AMQP 0.9.1 Model [1]. `1.0-beta10` is a development release with one fix release. We recommend all users to upgrade to it. ## Changes in 1.0.0-beta10 ### langohr.basic/reject now correctly uses basic.reject langohr.basic/reject now correctly uses `basic.reject` AMQP method and not `basic.ack`. Contributed by @natedev. ## Change Log Langohr change log [2] is available on GitHub. ## Thank You, Contributors * natedev [3] 1. http://bitly.com/amqp-model-explained 2. https://github.com/michaelklishin/langohr/blob/master/ChangeLog.md 3. http://github.com/natedev -- MK http://github.com/michaelklishin http://twitter.com/michaelklishin -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
compile fails but stack trace does not mention a line of code in my app
I am finding the following stack trace unusually devoid of information. My app is Clojure 1.3. I run lein compile and I get the following stack trace. Am I blind, or does this stack trace fail to tell me what line I should look at? lein compile Compiling who-is-logged-in.core Exception in thread main java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.Symbol at clojure.lang.RT.seqFrom(RT.java:487) at clojure.lang.RT.seq(RT.java:468) at clojure.lang.RT.first(RT.java:560) at clojure.core$first.invoke(core.clj:55) at clojure.core$map$fn__3811.invoke(core.clj:2432) at clojure.lang.LazySeq.sval(LazySeq.java:42) at clojure.lang.LazySeq.seq(LazySeq.java:60) at clojure.lang.RT.seq(RT.java:466) at clojure.core$seq.invoke(core.clj:133) at clojure.core$filter$fn__3830.invoke(core.clj:2468) at clojure.lang.LazySeq.sval(LazySeq.java:42) at clojure.lang.LazySeq.seq(LazySeq.java:60) at clojure.lang.RT.seq(RT.java:466) at clojure.core$seq.invoke(core.clj:133) at clojure.core$assert_valid_fdecl.invoke(core.clj:6464) at clojure.core$sigs.invoke(core.clj:220) at clojure.core$defn.doInvoke(core.clj:293) at clojure.lang.RestFn.invoke(RestFn.java:525) at clojure.lang.Var.invoke(Var.java:421) at clojure.lang.AFn.applyToHelper(AFn.java:185) at clojure.lang.Var.applyTo(Var.java:518) at clojure.lang.Compiler.macroexpand1(Compiler.java:6320) at clojure.lang.Compiler.macroexpand(Compiler.java:6381) at clojure.lang.Compiler.compile1(Compiler.java:6970) at clojure.lang.Compiler.compile(Compiler.java:7046) at clojure.lang.RT.compile(RT.java:385) at clojure.lang.RT.load(RT.java:425) at clojure.lang.RT.load(RT.java:398) at clojure.core$load$fn__4610.invoke(core.clj:5386) at clojure.core$load.doInvoke(core.clj:5385) at clojure.lang.RestFn.invoke(RestFn.java:408) at clojure.core$load_one.invoke(core.clj:5200) at clojure.core$compile$fn__4615.invoke(core.clj:5397) at clojure.core$compile.invoke(core.clj:5396) at user$eval27.invoke(NO_SOURCE_FILE:1) at clojure.lang.Compiler.eval(Compiler.java:6465) at clojure.lang.Compiler.eval(Compiler.java:6455) at clojure.lang.Compiler.eval(Compiler.java:6431) at clojure.core$eval.invoke(core.clj:2795) at clojure.main$eval_opt.invoke(main.clj:296) at clojure.main$initialize.invoke(main.clj:315) at clojure.main$null_opt.invoke(main.clj:348) at clojure.main$main.doInvoke(main.clj:426) at clojure.lang.RestFn.invoke(RestFn.java:421) at clojure.lang.Var.invoke(Var.java:405) at clojure.lang.AFn.applyToHelper(AFn.java:163) at clojure.lang.Var.applyTo(Var.java:518) at clojure.main.main(main.java:37) Compilation failed. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thursday, October 25, 2012 11:32:11 AM UTC-7, Jim foo.bar wrote: On 25/10/12 19:20, Raoul Duke wrote: On Thu, Oct 25, 2012 at 11:17 AM, Brian Craft craft...@gmail.comjavascript: wrote: http://www.ibm.com/developerworks/library/j-clojure-protocols/ since different protocols would collide. E.g. two shapes represented by maps are going to dispatch to the same area protocol, I think, since they're both maps. i suspect it shouldn't be a problem, since i thought protocols are to support specialization of function per (single dispatchy) type? Protocols go hand-in-hand with records in order to provide the fastest polymorphic behaviour possible which is no other that type-based dispatch...I still don't understand why you 'd want that from what you've described so far... Going back to your graphics example, I think I've had similar situation in one of my GUIs...I had a canva-react fn that worked for the game of chess but not for any other games. So yes, I made it a multi-method and now consumers of the lib that are supposed to build board-games with i,t can simply add their own canva-react that handles their game...Does this sound similar to what you're trying to do? Yes, it does. Ok, so: multimethods. Multimethods seem like a convenience layer over duck typing: probe the object to see what it is, then dispatch. Is that a fair description? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
No no this namespace is part of Clojure itself. How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. On Thursday, October 25, 2012 2:33:49 PM UTC-4, Jim foo.bar wrote: On 25/10/12 19:25, larry google groups wrote: So, in project.clj, I do this: [org.clojure/io] ? No no this namespace is part of Clojure itself. No need to put it in the project.clj. Just require it in your namespace where you want to use it... Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On 25/10/12 19:38, Brian Craft wrote: Multimethods seem like a convenience layer over duck typing: probe the object to see what it is, then dispatch. Is that a fair description? Not exactly...MUlti-methods have no limitations with regarding dispatch. You can dispatch on anything...I mean ANYTHING!!! To give you an idea, my canva-react mulit-method dispatches on the type of game being played at the moment which is not part of the parameters passed in!!! In other words the dispatch function completely ignores the arguments! Nothing to do with types/classes etc etc. You dispatch on some function - that is it!!! similarly: |(||defmulti||halt| |(||fn||[||_ _||]| |;dispatch-function checks for OS - ignores args | |(||let||[||os||(||System/getProperty||os.name||)||]| |||(||if||(||.startsWith os||Mac OS||)||:Linux ||(||keyword||os||)||)||)||)||)| |;;for Linux and Mac machines | |(||defmethod||halt :Linux||[||root-pwd minutes-after||]| |||(||clojure||.java.shell/sh| |||sudo||-S||shutdown||(||str||+||minutes-after||)||:in||(||str||root-pwd||\n||)||)||)| |;;for Windows machines| |(||defmethod||halt :Windows||[||_ minutes-after||]| |||(||clojure||.java.shell/sh||shutdown||-s||-t| |(||str||minutes-after||)||)||)| |;;for Solaris machines| |(||defmethod||halt :Solaris||[||root-pwd seconds-after||]| |||(||clojure||.java.shell/sh| |||shutdown||-S||-y||(||str||-g||seconds-after||)||-i||S||:in||(||str||root-pwd||\n||)||)||)| |;;in case nothing fires| |(||defmethod||halt||:default||[||]||(||throw||(||UnsupportedOperationException.||Unsupported operating system!||)||)||) Jim | -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 11:38 AM, Brian Craft craft.br...@gmail.com wrote: Multimethods seem like a convenience layer over duck typing: probe the object to see what it is, then dispatch. Is that a fair description? maybe if you squint. but i wouldn't have said so, just to my way of thinking. http://clojure.org/runtime_polymorphism -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: data.json 0.2.0
I agree these changes are for the best. Not announcing breaking changes is not optimal as it were, but we should solve the general problem, rather than this specific instance In a world with codeq, the capability exists to detect breaking changes. Both by library authors, and by their consumers. The key of course is to make this easy. A centralized, pre-imported codeq datomic database, and associated lein tasks, would be one way to do that. On Thu, Oct 25, 2012 at 11:08 AM, Stuart Sierra the.stuart.sie...@gmail.com wrote: I am not opposed to having a shim to support an API compatible with older releases. It's not even particularly difficult: https://gist.github.com/3950124 I certainly did not anticipate this release causing significant problems for application or library developers, and if it did then I apologize. However, I will stand by the decision to update the API. data.json 0.1.x suffered from what I consider, in retrospect, to be poor design decisions. Those were decisions I made over two years ago in a hasty effort to please too many people who had conflicting goals: - Converting field names to keywords by default can create invalid keywords. - Keywordization is controlled by a bare boolean argument with little indication of its function. - Inconsistent styles of optional arguments: read-json and write-json take booleans as bare arguments, json-str and print-json use keyword-value pairs. - Parsing a string and parsing from a stream -- two very different operations -- are conflated in a single function. - Functions are not consistently named: json-str, read-json, write-json - Function names repeat the name of the library, rather than using namespaces. It was impossible to solve some of these problems without introducing breaking changes. Looking at the Clojure Library Coding Standards[1], data.json 0.2.0 does a better job at Use good names and Unroll optional named arguments. It fails at Java's commitment to not break existing code. In this instance, I believe the tradeoff is worthwhile because the new API can be more easily extended with additional arguments. This also opened up a place to add new features such as customizable conversion functions, the most-commonly-requested feature for this library. Per Rich's directive[2], I cannot yet make a 1.0.0 release. Therefore, 0.1.3 to 0.2.0 is the largest version bump I can make and the best indication I can give of breaking changes. I hope that these improvements to the API bring this library closer to a 1.0.0-ready state. I'm not trying to make anyone's life more difficult, just trying to provide useful tools. -S [1]: http://dev.clojure.org/display/design/Library+Coding+Standards [2]: http://dev.clojure.org/display/design/Contrib+1.0.0+Releases -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: compile fails but stack trace does not mention a line of code in my app
Look in who-is-logged-in.core for errors On Thu, Oct 25, 2012 at 1:36 PM, larry google groups lawrencecloj...@gmail.com wrote: who-is-logged-in.core -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thursday, October 25, 2012 11:44:50 AM UTC-7, Jim foo.bar wrote: On 25/10/12 19:38, Brian Craft wrote: Multimethods seem like a convenience layer over duck typing: probe the object to see what it is, then dispatch. Is that a fair description? Not exactly...MUlti-methods have no limitations with regarding dispatch. You can dispatch on anything...I mean ANYTHING!!! To give you an idea, my canva-react mulit-method dispatches on the type of game being played at the moment which is not part of the parameters passed in!!! In other words the dispatch function completely ignores the arguments! Nothing to do with types/classes etc etc. You dispatch on some function - that is it!!! similarly: (defmulti halt (fn [_ _] ;dispatch-function checks for OS - ignores args (let [os (System/getProperty os.name)] (if (.startsWith os Mac OS) :Linux (keyword os) ;;for Linux and Mac machines (defmethod halt :Linux [root-pwd minutes-after] (clojure.java.shell/sh sudo -S shutdown (str + minutes-after) :in (str root-pwd \n)) ) ;;for Windows machines (defmethod halt :Windows [_ minutes-after] (clojure.java.shell/sh shutdown -s -t (str minutes-after))) ;;for Solaris machines (defmethod halt :Solaris [root-pwd seconds-after] (clojure.java.shell/sh shutdown -S -y (str -g seconds-after) -i S :in (str root-pwd \n))) ;;in case nothing fires (defmethod halt :default [] (throw (UnsupportedOperationException. Unsupported operating system!))) heh. I see. Thanks! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On 25/10/12 19:39, larry google groups wrote: How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. OK I'll grant you this...Documentation is not the strong part of Clojure. There have been/still are efforts to improve on this but generally any newcomer to the language struggles at first...A general rule of thumb is that if something starts with clojure.something.. chances are it is part of Clojure itself (there are exception though e.g clojure.java.jdbc)... hope that helps :-) Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: compile fails but stack trace does not mention a line of code in my app
On Thu, Oct 25, 2012 at 11:36 AM, larry google groups lawrencecloj...@gmail.com wrote: I am finding the following stack trace unusually devoid of information. My app is Clojure 1.3. I run lein compile and I get the following stack trace. Am I blind, or does this stack trace fail to tell me what line I should look at? lein compile is not very helpful in terms of debugging syntax errors. Working with source code in the REPL is sometimes easier to debug (sometimes!). My guess would be a syntax error in your (ns ...) declaration tho'... -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: [ANN] nrepl.el 0.1.5 released
Very useful, thank you very much Tim! Il giorno giovedì 25 ottobre 2012 19:10:22 UTC+2, Tim King ha scritto: Thanks everyone for all the positive feedback. Glad to hear the community is finding this useful. Cheers, Tim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On Thu, Oct 25, 2012 at 11:39 AM, larry google groups lawrencecloj...@gmail.com wrote: How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. http://clojure.github.com If it's listed separated there, it's a contrib you need to pull in explicitly. Otherwise it's part of Clojure itself. Clojure's namespaces are documented here (linked from 'clojure' in the left column of the above page): http://clojure.github.com/clojure/ -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On 25/10/12 19:57, Sean Corfield wrote: On Thu, Oct 25, 2012 at 11:39 AM, larry google groups lawrencecloj...@gmail.com wrote: How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. http://clojure.github.com If it's listed separated there, it's a contrib you need to pull in explicitly. Otherwise it's part of Clojure itself. Clojure's namespaces are documented here (linked from 'clojure' in the left column of the above page): http://clojure.github.com/clojure/ Nice... : This definitely more informative than what I suggested! :-[ Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: compile fails but stack trace does not mention a line of code in my app
Since we're wild mass guessing, I'd say from that stack trace that there's invalid syntax in a defn's signature somewhere. I'm basing this on the references to clojure.core$defn and clojure.core$sigs shortly above compile and macroexpand. Phil On Oct 25, 2012 7:36 PM, larry google groups lawrencecloj...@gmail.com wrote: I am finding the following stack trace unusually devoid of information. My app is Clojure 1.3. I run lein compile and I get the following stack trace. Am I blind, or does this stack trace fail to tell me what line I should look at? lein compile Compiling who-is-logged-in.core Exception in thread main java.lang.IllegalArgumentException: Don't know how to create ISeq from: clojure.lang.Symbol at clojure.lang.RT.seqFrom(RT.java:487) at clojure.lang.RT.seq(RT.java:468) at clojure.lang.RT.first(RT.java:560) at clojure.core$first.invoke(core.clj:55) at clojure.core$map$fn__3811.invoke(core.clj:2432) at clojure.lang.LazySeq.sval(LazySeq.java:42) at clojure.lang.LazySeq.seq(LazySeq.java:60) at clojure.lang.RT.seq(RT.java:466) at clojure.core$seq.invoke(core.clj:133) at clojure.core$filter$fn__3830.invoke(core.clj:2468) at clojure.lang.LazySeq.sval(LazySeq.java:42) at clojure.lang.LazySeq.seq(LazySeq.java:60) at clojure.lang.RT.seq(RT.java:466) at clojure.core$seq.invoke(core.clj:133) at clojure.core$assert_valid_fdecl.invoke(core.clj:6464) at clojure.core$sigs.invoke(core.clj:220) at clojure.core$defn.doInvoke(core.clj:293) at clojure.lang.RestFn.invoke(RestFn.java:525) at clojure.lang.Var.invoke(Var.java:421) at clojure.lang.AFn.applyToHelper(AFn.java:185) at clojure.lang.Var.applyTo(Var.java:518) at clojure.lang.Compiler.macroexpand1(Compiler.java:6320) at clojure.lang.Compiler.macroexpand(Compiler.java:6381) at clojure.lang.Compiler.compile1(Compiler.java:6970) at clojure.lang.Compiler.compile(Compiler.java:7046) at clojure.lang.RT.compile(RT.java:385) at clojure.lang.RT.load(RT.java:425) at clojure.lang.RT.load(RT.java:398) at clojure.core$load$fn__4610.invoke(core.clj:5386) at clojure.core$load.doInvoke(core.clj:5385) at clojure.lang.RestFn.invoke(RestFn.java:408) at clojure.core$load_one.invoke(core.clj:5200) at clojure.core$compile$fn__4615.invoke(core.clj:5397) at clojure.core$compile.invoke(core.clj:5396) at user$eval27.invoke(NO_SOURCE_FILE:1) at clojure.lang.Compiler.eval(Compiler.java:6465) at clojure.lang.Compiler.eval(Compiler.java:6455) at clojure.lang.Compiler.eval(Compiler.java:6431) at clojure.core$eval.invoke(core.clj:2795) at clojure.main$eval_opt.invoke(main.clj:296) at clojure.main$initialize.invoke(main.clj:315) at clojure.main$null_opt.invoke(main.clj:348) at clojure.main$main.doInvoke(main.clj:426) at clojure.lang.RestFn.invoke(RestFn.java:421) at clojure.lang.Var.invoke(Var.java:405) at clojure.lang.AFn.applyToHelper(AFn.java:163) at clojure.lang.Var.applyTo(Var.java:518) at clojure.main.main(main.java:37) Compilation failed. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On 25/10/12 19:49, Brian Craft wrote: heh. I see. Thanks! No problem...;-) Jim ps: It goes without saying that you shouldn't sprinkle your code with multi-methods just because you can! Trust me, I know they are nice and very tempting to use but save them for when you truly need multiple-dispatch and generally not for performance critical code. All the freedom/leverage they provide comes at a cost... For drawing things on screen it's fine... -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Generating permutations in core.logic
Hi, I'm new to core.logic and logic programming in general. I tried to write a small program to generate all permutations of any size for an input list with unique elements. To start, I hardcoded the input list to be (range 3). Here's what I came up with: (defne everyo [g l] A relation that guarantees that g holds for all elements of l. ([_ ()]) ([_ [x . r]] (g x) (everyo g r))) (run 16 [q] (everyo #(membero % (range 3)) q) (distincto q)) ;; returns (() (0) (1) (2) (0 1) (1 0) (2 0) (0 2) (2 1) (1 2) (2 0 1) (2 1 0) (0 2 1) (1 2 0) (0 1 2) (1 0 2)), as expected This program works: it returns all 16 permutations of '(0 1 2). However, if I ask for any more than 16 solutions, the program doesn't terminate. Having browsed this mailing list a little, I noticed a warning about using recursive relations first, so I swapped the two clauses of the run clause: (run 16 [q] (distincto q) (everyo #(membero % (range 3)) q)) ;; returns (() [0] [1] [2] (0 0) (0 1) (1 0) (0 2) (1 1) (2 0) (1 2) (2 1) (2 2) (0 0 0) (0 0 1) (0 1 0)), incorrect This program returns a different result from the first one. The lists it returns are no longer distinct, despite declaring that q must be distincto. Additionally, the singleton lists are vectors for some reason. Asking for more than 16 results now terminates, but returns more incorrect (non-distinct) result lists. Clearly I'm doing something wrong. I suspect that my implementation of everyo is flawed somehow. Can someone please offer advice? Thanks, Jordan Lewis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
I think you want to have a look at clojure.math.combinatorics Jim On 25/10/12 20:10, Jordan Lewis wrote: Hi, I'm new to core.logic and logic programming in general. I tried to write a small program to generate all permutations of any size for an input list with unique elements. To start, I hardcoded the input list to be (range 3). Here's what I came up with: (defne everyo [g l] A relation that guarantees that g holds for all elements of l. ([_ ()]) ([_ [x . r]] (g x) (everyo g r))) (run 16 [q] (everyo #(membero % (range 3)) q) (distincto q)) ;; returns (() (0) (1) (2) (0 1) (1 0) (2 0) (0 2) (2 1) (1 2) (2 0 1) (2 1 0) (0 2 1) (1 2 0) (0 1 2) (1 0 2)), as expected This program works: it returns all 16 permutations of '(0 1 2). However, if I ask for any more than 16 solutions, the program doesn't terminate. Having browsed this mailing list a little, I noticed a warning about using recursive relations first, so I swapped the two clauses of the run clause: (run 16 [q] (distincto q) (everyo #(membero % (range 3)) q)) ;; returns (() [0] [1] [2] (0 0) (0 1) (1 0) (0 2) (1 1) (2 0) (1 2) (2 1) (2 2) (0 0 0) (0 0 1) (0 1 0)), incorrect This program returns a different result from the first one. The lists it returns are no longer distinct, despite declaring that q must be distincto. Additionally, the singleton lists are vectors for some reason. Asking for more than 16 results now terminates, but returns more incorrect (non-distinct) result lists. Clearly I'm doing something wrong. I suspect that my implementation of everyo is flawed somehow. Can someone please offer advice? Thanks, Jordan Lewis -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On Thu, Oct 25, 2012 at 3:10 PM, Jordan Lewis jordanthele...@gmail.comwrote: Hi, I'm new to core.logic and logic programming in general. I tried to write a small program to generate all permutations of any size for an input list with unique elements. To start, I hardcoded the input list to be (range 3). Here's what I came up with: Are you using core.logic 0.8.0-beta1 ? The distincto issue looks like it might be a bug. As far as not terminating that's because of the structure of the program. By asking for the 17th solution you asking to construct lists larger than 3 which satisfy the distincto condition which is of course impossible. The program fails indefinitely because q has no bound. David -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On Thu, Oct 25, 2012 at 3:27 PM, David Nolen dnolen.li...@gmail.com wrote: On Thu, Oct 25, 2012 at 3:10 PM, Jordan Lewis jordanthele...@gmail.comwrote: Hi, I'm new to core.logic and logic programming in general. I tried to write a small program to generate all permutations of any size for an input list with unique elements. To start, I hardcoded the input list to be (range 3). Here's what I came up with: You can bound the q w/: (bounded-listo q n) n must be ground or you will continue to run into trouble. David -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On Thu, Oct 25, 2012 at 3:10 PM, Jordan Lewis jordanthele...@gmail.comwrote: (run 16 [q] (distincto q) (everyo #(membero % (range 3)) q)) ;; returns (() [0] [1] [2] (0 0) (0 1) (1 0) (0 2) (1 1) (2 0) (1 2) (2 1) (2 2) (0 0 0) (0 0 1) (0 1 0)), incorrect Ticket created for the distincto bug - http://dev.clojure.org/jira/browse/LOGIC-62 -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
Sent from a smartphone, please excuse the brevity/typos. Le 25 oct. 2012 à 20:44, Jim - FooBar(); jimpil1...@gmail.com a écrit : On 25/10/12 19:38, Brian Craft wrote: Multimethods seem like a convenience layer over duck typing: probe the object to see what it is, then dispatch. Is that a fair description? Not exactly...MUlti-methods have no limitations with regarding dispatch. You can dispatch on anything...I mean ANYTHING!!! To give you an idea, my canva-react mulit-method dispatches on the type of game being played at the moment which is not part of the parameters passed in!!! In other words the dispatch function completely ignores the arguments! Wow, this kind of decision is not for the faint of heart. Not to be taken lightly, that's for sure! Because then, your code becomes non pure, harder to test, etc. not saying that it was not appropriate in your case, but rather than used as a demonstration of how 'powerful' (as in easy to shoot one selves in the foot), this should certainly not be a habit to start using this kind of trick at first... Nothing to do with types/classes etc etc. You dispatch on some function - that is it!!! similarly: (defmulti halt (fn [_ _] ;dispatch-function checks for OS - ignores args (let [os (System/getProperty os.name)] (if (.startsWith os Mac OS) :Linux (keyword os) ;;for Linux and Mac machines (defmethod halt :Linux [root-pwd minutes-after] (clojure.java.shell/sh sudo -S shutdown (str + minutes-after) :in (str root-pwd \n))) ;;for Windows machines (defmethod halt :Windows [_ minutes-after] (clojure.java.shell/sh shutdown -s -t (str minutes-after))) ;;for Solaris machines (defmethod halt :Solaris [root-pwd seconds-after] (clojure.java.shell/sh shutdown -S -y (str -g seconds-after) -i S :in (str root-pwd \n))) ;;in case nothing fires (defmethod halt :default [] (throw (UnsupportedOperationException. Unsupported operating system!))) Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Disconnect a downstream channel in lamina
If the upstream channel is permanent, then it won't close if all downstream channels are closed. You can create a permanent channel using (permanent-channel) or (channel* :permanent? true). Once you have that, you can replace all that code with a simple (siphon perm-ch conn-ch) As an aside, though, you could also accomplish the above without delving into functions that are really implementation details. (if-let [evs (seq (channel-seq ch))] evs (run-pipeline (read-channel* :on-timeout ::timeout, timeout POLL-TIMEOUT) (fn [msg] (when-not (= ::timeout msg) (conj (channel-seq ch) msg) This is non-blocking, but will require some outer handler to deal with the async-result. Also, in the future you'll probably get a more reliable reply if you use the Aleph mailing list. Zach On Thursday, October 25, 2012 4:09:40 AM UTC-7, Marko Topolnik wrote: I use lamina channels in a library that maintains multiple event streams. The event source is the Asterisk Management Interface, whose raw events are processed, filtered, collated, and finally pushed into appropriate lamina channels. On the client side of my library I want to expose the event streams as a web service. My challenge is to implement long polling: a request either finds events already enqueued, returning immediately; or blocks until an event occurs (with a timeout), then accumulates any further events for a short period, then returns the accumulated events. This reduces network overhead for the typical case of events occuring in short bursts (a single user action triggers several events). I have implemented this behavior in a piece of code that occupies its thread for the entire duration of the request: (require [lamina.core :as m] [lamina.core.graph.node :as node] [lamina.core.channel :as chan]) (let [evs (node/drain (chan/emitter-node ch)) evs (if (seq evs) evs (try (let [ev @(m/with-timeout POLL-TIMEOUT (m/read-channel ch))] (Thread/sleep EVENT-BURST-PERIOD) (conj (node/drain (chan/emitter-node ch)) ev)) (catch TimeoutException _ nil)))] (vec evs)) I would instead like to do this without blocking the thread. Ideally, I'll use aleph to implement the web service and connect a downstream HTTP response channel to my library's lamina channel. What I'm missing is, how do I disconnect the downstream channel without breaking anything in the upstream channel? I want to cleanly disconnect it, let my channel enqueue any further events, then later connect another aleph channel, which will drain those events with no loss. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On 25/10/12 20:33, Laurent PETIT wrote: Wow, this kind of decision is not for the faint of heart. Not to be taken lightly, that's for sure! Because then, your code becomes non pure, harder to test, etc. not saying that it was not appropriate in your case, but rather than used as a demonstration of how 'powerful' (as in easy to shoot one selves in the foot), this should certainly not be a habit to start using this kind of trick at first... Yes you're right...suddenly the multi-method depends on some state, however the GUI is already pretty stateful and if you want to let the user write the logic of a game and suddenly show it up with graphics on the screen without writing any code, I don't see how else it can be done...It's not critical code, it's extensible, it's powerful... The point I was trying to make and perhaps I was a bit extreme, is that there is no type, there is no class, there is no object - it's just a function! Usually you dispatch on some fn of the arguments or some of arguments or if you really want to some other irrelevant var (state). Ignoring the arguments clearly makes the point that (perhaps too hard): forget anything you knew about single type-based dispatch. Multi-methods are on a whole other level with regards to polymorphism. :-) Jim ps: I hope we can agree that there is nothing wrong with the 'halt' multi-method I demonstrated as it depends on some state already and doesn't need to know about passwords and minutes. Because the arity of dispatch-fn has to match the arty of the implementations it is a common thing to ignore some arguments in dispatch-fns isn't it? I've seen quite a few times... -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
Okay, if I look here: http://clojure.github.com Can I assume that anything that starts with clojure.core is not a dependency? And everything else is? So this would be listed as a dependency if I use it: clojure.test.junithttp://clojure.github.com/clojure/clojure.test.junit-api.html but I would not have to list this as a dependency: clojure.core.protocolshttp://clojure.github.com/clojure/clojure.core.protocols-api.html On Thursday, October 25, 2012 2:57:26 PM UTC-4, Sean Corfield wrote: On Thu, Oct 25, 2012 at 11:39 AM, larry google groups lawrenc...@gmail.com javascript: wrote: How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. http://clojure.github.com If it's listed separated there, it's a contrib you need to pull in explicitly. Otherwise it's part of Clojure itself. Clojure's namespaces are documented here (linked from 'clojure' in the left column of the above page): http://clojure.github.com/clojure/ -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On Thursday, October 25, 2012 3:17:44 PM UTC-4, Jim foo.bar wrote: I think you want to have a look at clojure.math.combinatorics Jim, thanks for the suggestion. I am trying to get a feel for how core.logic works, not reinvent code from the combinatorics library. On Thursday, October 25, 2012 3:27:40 PM UTC-4, David Nolen wrote: Are you using core.logic 0.8.0-beta1 ? The distincto issue looks like it might be a bug. Yes. As far as not terminating that's because of the structure of the program. By asking for the 17th solution you asking to construct lists larger than 3 which satisfy the distincto condition which is of course impossible. The program fails indefinitely because q has no bound. Ah, I see. That's interesting. I had assumed that the two clauses would naturally create a bound on the size of the list, but I suppose that it's not enough information to go on. On Thursday, October 25, 2012 3:31:25 PM UTC-4, David Nolen wrote: Ticket created for the distincto bug - http://dev.clojure.org/jira/browse/LOGIC-62 Thanks! - Jordan -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On 25/10/12 20:57, Jordan Lewis wrote: Jim, thanks for the suggestion. I am trying to get a feel for how core.logic works, not reinvent code from the combinatorics library. Fair enough... :-) Jim -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
(fn [_ _] ;dispatch-function checks for OS - ignores args (let [os (System/getProperty os.name)] (if (.startsWith os Mac OS) :Linux (keyword os) This seems like a very poor use of multi-methods. Multi-methods exist to provide both dynamic and open dispatch. In this case, the dispatch function is completely static. If you don't need dynamism or openness, then you're better off with a simple case form at the top level: (case platform :linux (def halt [root-pwd minutes-after] ...) :windows ... ... (def halt [ args] (throw ...))) If you prefer the appearance of top-level forms, or need the openness, you could pretty easily implement a static version of defmulti defmethod which ensure you only pay the dispatch cost once at startup, rather than on every invocation. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
Anything that starts with clojure. is part of (some version of) clojure. For Clojure 1.4, that's everything listed in Table of Contents on the right side of the web page you'll find here: http://clojure.github.com/clojure/ clojure.core clojure.data clojure.inspector clojure.java.browse clojure.java.io clojure.java.javadoc clojure.java.shell clojure.main clojure.pprint clojure.reflect clojure.repl clojure.set clojure.stacktrace clojure.string clojure.template clojure.test clojure.walk clojure.xml clojure.zip That'll all be available without needing to add dependencies to your project.clj. You'll just need to :require it as usual in your ns form. On Thu, Oct 25, 2012 at 9:52 PM, larry google groups lawrencecloj...@gmail.com wrote: Okay, if I look here: http://clojure.github.com Can I assume that anything that starts with clojure.core is not a dependency? And everything else is? So this would be listed as a dependency if I use it: clojure.test.junit but I would not have to list this as a dependency: clojure.core.protocols On Thursday, October 25, 2012 2:57:26 PM UTC-4, Sean Corfield wrote: On Thu, Oct 25, 2012 at 11:39 AM, larry google groups lawrenc...@gmail.com wrote: How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. http://clojure.github.com If it's listed separated there, it's a contrib you need to pull in explicitly. Otherwise it's part of Clojure itself. Clojure's namespaces are documented here (linked from 'clojure' in the left column of the above page): http://clojure.github.com/clojure/ -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
You say that from the safe standpoint of being able to enumerate all OSes in advance...I can imagine a world where anyone can have his own OS. :-) Seriously now, this is not production code obviously! just a demo... Jim On 25/10/12 21:04, Brandon Bloom wrote: |(||fn||[||_ _||]||;dispatch-function checks for OS - ignores args| |(||let||[||os||(||System/getProperty||os.name http://os.name||)||]| |||(||if||(||.startsWith os||Mac OS||)||:Linux ||(||keyword||os||)||)||)||)||)| This seems like a very poor use of multi-methods. Multi-methods exist to provide both dynamic and open dispatch. In this case, the dispatch function is completely static. If you don't need dynamism or openness, then you're better off with a simple case form at the top level: (case platform :linux (def halt [root-pwd minutes-after] ...) :windows ... ... (def halt [ args] (throw ...))) If you prefer the appearance of top-level forms, or need the openness, you could pretty easily implement a static version of defmulti defmethod which ensure you only pay the dispatch cost once at startup, rather than on every invocation. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: data.json 0.2.0
I'm sorry for causing people extra work. How's this for a solution: https://github.com/clojure/data.json/commit/6ee71009946731d89ef8f98e7b659fa82443b6a2 This allows the 0.2.x code to pass all the tests for data.json 0.1.3. I can't retract the 0.2.0 release, but if I push this out as 0.2.1 the compatibility issues should be at a minimum. -S -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: pst shows the cause instead of the last thrown ex thus it doesn't show the chain
I can see why, here's the implementation of pst:
(defn pst
Prints a stack trace of the exception, to the depth requested. If none
supplied, uses the root cause of the
most recent repl exception (*e), and a depth of 12.
{:added 1.3}
([] (pst 12))
([e-or-depth]
(if (instance? Throwable e-or-depth)
(pst e-or-depth 12)
(when-let [e *e]
(pst (root-cause e) e-or-depth
([^Throwable e depth]
(binding [*out* *err*]
(println (str (- e class .getSimpleName)
(.getMessage e)
(when-let [info (ex-data e)] (str (pr-str info)
(let [st (.getStackTrace e)
cause (.getCause e)]
(doseq [el (take depth
(remove #(#{clojure.lang.RestFn
clojure.lang.AFn} (.getClassName %))
st))]
(println (str \tab (stack-element-str el
(when cause
(println Caused by:)
(pst cause (min depth
(+ 2 (- (count (.getStackTrace cause))
(count st))
so this works as expected:
= *(try (throw (Exception. a (Exception. cause))) (catch Exception e
(throw e)))
(pst *e 123912031)*
Exception cause cloj2.ka/eval1430 (NO_SOURCE_FILE:1)
Exception a
cloj2.ka/eval1430 (NO_SOURCE_FILE:1)
clojure.lang.Compiler.eval (Compiler.java:6603)
clojure.lang.Compiler.eval (Compiler.java:6566)
clojure.core/eval (core.clj:2836)
clojure.main/repl/read-eval-print--6667 (main.clj:245)
clojure.main/repl/fn--6672/fn--6673 (main.clj:266)
clojure.main/repl/fn--6672 (main.clj:266)
clojure.main/repl (main.clj:264)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate/fn--938
(interruptible_eval.clj:58)
clojure.core/apply (core.clj:614)
clojure.core/with-bindings* (core.clj:1785)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate
(interruptible_eval.clj:43)
clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval/fn--979/fn--982
(interruptible_eval.clj:173)
clojure.core/comp/fn--4092 (core.clj:2314)
clojure.tools.nrepl.middleware.interruptible-eval/run-next/fn--972
(interruptible_eval.clj:140)
java.util.concurrent.ThreadPoolExecutor.runWorker
(ThreadPoolExecutor.java:1110)
java.util.concurrent.ThreadPoolExecutor$Worker.run
(ThreadPoolExecutor.java:603)
java.lang.Thread.run (Thread.java:722)
Caused by:
Exception cause
cloj2.ka/eval1430 (NO_SOURCE_FILE:1)
clojure.lang.Compiler.eval (Compiler.java:6603)
nil
but this doesn't:
= *(try (throw (Exception. a (Exception. cause))) (catch Exception e
(throw e)))
(pst 123912031)*
Exception cause cloj2.ka/eval1434 (NO_SOURCE_FILE:1)
Exception cause
cloj2.ka/eval1434 (NO_SOURCE_FILE:1)
clojure.lang.Compiler.eval (Compiler.java:6603)
clojure.lang.Compiler.eval (Compiler.java:6566)
clojure.core/eval (core.clj:2836)
clojure.main/repl/read-eval-print--6667 (main.clj:245)
clojure.main/repl/fn--6672/fn--6673 (main.clj:266)
clojure.main/repl/fn--6672 (main.clj:266)
clojure.main/repl (main.clj:264)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate/fn--938
(interruptible_eval.clj:58)
clojure.core/apply (core.clj:614)
clojure.core/with-bindings* (core.clj:1785)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate
(interruptible_eval.clj:43)
clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval/fn--979/fn--982
(interruptible_eval.clj:173)
clojure.core/comp/fn--4092 (core.clj:2314)
clojure.tools.nrepl.middleware.interruptible-eval/run-next/fn--972
(interruptible_eval.clj:140)
java.util.concurrent.ThreadPoolExecutor.runWorker
(ThreadPoolExecutor.java:1110)
java.util.concurrent.ThreadPoolExecutor$Worker.run
(ThreadPoolExecutor.java:603)
java.lang.Thread.run (Thread.java:722)
nil
On Wed, Oct 24, 2012 at 3:27 PM, AtKaaZ atk...@gmail.com wrote:
Here, (pst) doesn't see the thrown exception which is a, it's seeing
only it's cause:
= *(try (throw (Exception. a (Exception. cause))) (catch Exception e
(throw e)))* *(pst 123912031)*
Exception cause datest1.core/eval3129 (NO_SOURCE_FILE:1)
Exception cause
datest1.core/eval3129 (NO_SOURCE_FILE:1)
clojure.lang.Compiler.eval (Compiler.java:6603)
clojure.lang.Compiler.eval (Compiler.java:6566)
clojure.core/eval (core.clj:2836)
clojure.main/repl/read-eval-print--6667 (main.clj:245)
clojure.main/repl/fn--6672/fn--6673 (main.clj:266)
clojure.main/repl/fn--6672 (main.clj:266)
clojure.main/repl (main.clj:264)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate/fn--938
(interruptible_eval.clj:58)
clojure.core/apply (core.clj:614)
clojure.core/with-bindings* (core.clj:1785)
clojure.tools.nrepl.middleware.interruptible-eval/evaluate
(interruptible_eval.clj:43)
clojure.tools.nrepl.middleware.interruptible-eval/interruptible-eval/fn--979/fn--982
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 11:38 AM, Brian Craft craft.br...@gmail.com wrote:
Multimethods seem like a convenience layer over duck typing: probe the
object to see what it is, then dispatch. Is that a fair description?
I think that's pretty accurate. Others have pointed out that multimethods
can potentially do more than that, but commonly, it's just a way to do
dispatch that leaves things open for extension.
Here's the vanilla way to do dispatch with no special constructs:
(defn circle [radius]
{:tag :circle, :radius radius})
(defn square [length]
{:tag :square, :length length})
(defn rectangle [length width]
{:tag :rectangle, :length length, :width width})
(defn tag-test [tag]
#(= (:tag %) tag))
(def circle? (tag-test :circle))
(def square? (tag-test :square))
(def rectangle? (tag-test :rectangle))
(defn area-circle [{:keys [radius]}]
(* 3.14 radius radius))
(defn area-square [{:keys [length]}]
(* length length))
(defn area-rectangle [{:keys [length width]}]
(* length width))
(defn area [shape]
(cond
(circle? shape) (area-circle shape)
(square? shape) (area-square shape)
(rectangle? shape) (area-rectangle shape)))
Here's the way with multimethods:
(defn circle [radius]
{:tag :circle, :radius radius})
(defn square [length]
{:tag :square, :length length})
(defn rectangle [length width]
{:tag :rectangle, :length length, :width width})
(defmulti area :tag)
(defmethod area :circle [{:keys [radius]}]
(* 3.14 radius radius))
(defmethod area :square [{:keys [length]}]
(* length length))
(defmethod area :rectangle [{:keys [length width]}]
(* length width))
The dispatch function has been eliminated, and we might not need to build
explicit predicates to test for the different types (although in a real
system, you'd probably want those anyway). Other than that, pretty
similar. Multimethods become a clearer win if you need inheritance, or if
you need other people to be able to extend the definition of area to new
types without access to your code.
Now let's look at the record version:
(defrecord Circle [radius])
(defrecord Square [length])
(defrecord Rectangle [length width])
(defn area-circle [{:keys [radius]}]
(* 3.14 radius radius))
(defn area-square [{:keys [length]}]
(* length length))
(defn area-rectangle [{:keys [length width]}]
(* length width))
;; Dispatch via protocol
(defprotocol Area
(area [this]))
(extend Circle
Area
{:area area-circle})
(extend Square
Area
{:area area-square})
(extend Rectangle
Area
{:area area-rectangle})
There are actually several ways to extend protocols to various records.
The most extensible way is to extend records from the outside like above,
and to use maps of functions so the functions aren't locked up inside the
record but can be reused by other related objects. But as you can see,
this is fairly verbose and it doesn't give you the kind of speed advantage
that people are generally looking for when they convert to
records/protocols. So most people end up declaring everything inline, like
this:
(defprotocol Area
(area [this]))
(defrecord Circle [radius]
Area
(area [_] (* 3.14 radius radius)))
(defrecord Square [length]
Area
(area [_] (* length length)))
(defrecord Rectangle [length width]
Area
(area [_] (* length width)))
I personally haven't had a very good experience with records and protocols,
although it is possible that they have improved since I last did much with
them. First, I found that records were mostly similar to maps, but behaved
subtly different in ways that bit me occasionally. Second, the
introduction and repetition of protocol names feel clunky to me, especially
in the common case of one function per protocol. Third, in order to chase
after the supposed performance gains that records/protocols purportedly
bring, I found myself altering my code in ways that looked less and less
Clojurian, using more dot syntax to access constructors, fields, and
methods, and adding type hints. Even with all those changes, I seemed to
keep running into places that Clojure was forced to use dynamic reflection
on my record-based code (which is never a problem with maps), and the
reflection more than cancels out any performance gains from the dispatch.
So my vote is for multimethods, which is at least as clean and fast as
manual dispatch with more flexibility. Records/protocols may have some
additional performance benefits in the right use cases, but in my
experience it definitely comes at a cost.
--
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Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On Thursday, October 25, 2012 2:39:33 PM UTC-4, larry google groups wrote: No no this namespace is part of Clojure itself. How do you know this? Where is this documented? I find myself baffled as to what is a dependency and what is not. Hi Larry, Note that, concerning libraries, there's three separate but often similar names to be aware of: * the lib's artifact-id (you'll find it at the top of the lib's very own project.clj). * the lib's github project name (if it's hosted there) * the namespace(s) that the lib provides (specified in the lib's source file(s) in the `ns` macro) Threre's also the lib's group-id, which --- if different from the artifact-id --- is also noted at the top of a lib's project.clj file. You use a lib's group-id and artifact-id in your own project.clj when you specify dependencies (group-id is left out when it's the same as the artifact-id, which is common for many 3rd-party Clojure libs). You use a lib's namespace name(s) in your own source's `ns` macro to use that lib in your code. Some notes about contrib libs: * all have a group-id of org.clojure, and * all have github project names like foo.bar (ex. math.combinatorics), under https://github.com/clojure * all have namespace names like clojure.foo.bar (ex. clojure.math.combinatorics). * they're hosted at maven central, not at clojars * you can find them all listed at http://dev.clojure.org/display/doc/Clojure+Contrib Some notes about 3rd-party Clojure libs: * many have a group-id the same as their artifact-id * most are hosted at github, and usually the github project name is the same as the artifact-id * most are available at Clojars via leiningen * many have a namespace like my-proj.core (Anyone: If there's any errors there, please let me know!) ---John -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On Thursday, October 25, 2012 5:04:23 PM UTC-4, John Gabriele wrote: Some notes about contrib libs: * all have a group-id of org.clojure, and * all have github project names like foo.bar (ex. math.combinatorics), under https://github.com/clojure * all have namespace names like clojure.foo.bar (ex. clojure.math.combinatorics). * they're hosted at maven central, not at clojars * you can find them all listed at http://dev.clojure.org/display/doc/Clojure+Contrib Oooh, one more bullet point for contrib libs: * they don't have a project.clj file. They use a pom.xml file instead! Thought I'd add that, being that it's so close to Halloween and all. ;) Some notes about 3rd-party Clojure libs: * many have a group-id the same as their artifact-id * most are hosted at github, and usually the github project name is the same as the artifact-id * most are available at Clojars via leiningen * many have a namespace like my-proj.core Most of these are, of course, managed by Leiningen and so *do* have a project.clj file. ---John -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thursday, October 25, 2012 1:49:53 PM UTC-7, puzzler wrote:
On Thu, Oct 25, 2012 at 11:38 AM, Brian Craft craft...@gmail.comjavascript:
wrote:
Multimethods seem like a convenience layer over duck typing: probe the
object to see what it is, then dispatch. Is that a fair description?
I think that's pretty accurate. Others have pointed out that
multimethods can potentially do more than that, but commonly, it's just a
way to do dispatch that leaves things open for extension.
Here's the vanilla way to do dispatch with no special constructs:
(defn circle [radius]
{:tag :circle, :radius radius})
(defn square [length]
{:tag :square, :length length})
(defn rectangle [length width]
{:tag :rectangle, :length length, :width width})
(defn tag-test [tag]
#(= (:tag %) tag))
(def circle? (tag-test :circle))
(def square? (tag-test :square))
(def rectangle? (tag-test :rectangle))
(defn area-circle [{:keys [radius]}]
(* 3.14 radius radius))
(defn area-square [{:keys [length]}]
(* length length))
(defn area-rectangle [{:keys [length width]}]
(* length width))
(defn area [shape]
(cond
(circle? shape) (area-circle shape)
(square? shape) (area-square shape)
(rectangle? shape) (area-rectangle shape)))
Here's the way with multimethods:
(defn circle [radius]
{:tag :circle, :radius radius})
(defn square [length]
{:tag :square, :length length})
(defn rectangle [length width]
{:tag :rectangle, :length length, :width width})
(defmulti area :tag)
(defmethod area :circle [{:keys [radius]}]
(* 3.14 radius radius))
(defmethod area :square [{:keys [length]}]
(* length length))
(defmethod area :rectangle [{:keys [length width]}]
(* length width))
The dispatch function has been eliminated, and we might not need to build
explicit predicates to test for the different types (although in a real
system, you'd probably want those anyway). Other than that, pretty
similar. Multimethods become a clearer win if you need inheritance, or if
you need other people to be able to extend the definition of area to new
types without access to your code.
Now let's look at the record version:
(defrecord Circle [radius])
(defrecord Square [length])
(defrecord Rectangle [length width])
(defn area-circle [{:keys [radius]}]
(* 3.14 radius radius))
(defn area-square [{:keys [length]}]
(* length length))
(defn area-rectangle [{:keys [length width]}]
(* length width))
;; Dispatch via protocol
(defprotocol Area
(area [this]))
(extend Circle
Area
{:area area-circle})
(extend Square
Area
{:area area-square})
(extend Rectangle
Area
{:area area-rectangle})
There are actually several ways to extend protocols to various records.
The most extensible way is to extend records from the outside like above,
and to use maps of functions so the functions aren't locked up inside the
record but can be reused by other related objects. But as you can see,
this is fairly verbose and it doesn't give you the kind of speed advantage
that people are generally looking for when they convert to
records/protocols. So most people end up declaring everything inline, like
this:
(defprotocol Area
(area [this]))
(defrecord Circle [radius]
Area
(area [_] (* 3.14 radius radius)))
(defrecord Square [length]
Area
(area [_] (* length length)))
(defrecord Rectangle [length width]
Area
(area [_] (* length width)))
I personally haven't had a very good experience with records and
protocols, although it is possible that they have improved since I last did
much with them. First, I found that records were mostly similar to maps,
but behaved subtly different in ways that bit me occasionally. Second, the
introduction and repetition of protocol names feel clunky to me, especially
in the common case of one function per protocol. Third, in order to chase
after the supposed performance gains that records/protocols purportedly
bring, I found myself altering my code in ways that looked less and less
Clojurian, using more dot syntax to access constructors, fields, and
methods, and adding type hints. Even with all those changes, I seemed to
keep running into places that Clojure was forced to use dynamic reflection
on my record-based code (which is never a problem with maps), and the
reflection more than cancels out any performance gains from the dispatch.
So my vote is for multimethods, which is at least as clean and fast as
manual dispatch with more flexibility. Records/protocols may have some
additional performance benefits in the right use cases, but in my
experience it definitely comes at a cost.
Thanks, this is very helpful!
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(if (io/file path-to-session-file) -- returns false though file exists
So, again, I'm trying to use Clojure to rebuild a PHP site. Right now I need the Clojure code to read the PHP session files. In the below function, I have a println that shows me that the path points to a file that really does exist. And yet this if() clause seems to always return false. (defn does-session-exist? [session-id] (let [path-to-session-file (str /var/lib/php5/sess_ session-id)] (println path-to-session-file) (if (io/file path-to-session-file) true false))) io is an alias: (:require [clojure.string :as st] [clojure.java.io :as io] [clojure.data.json :as json] [who-is-logged-in.memory_display :as who]) I look here and see that the old monolithic Clojure contrib had an exists function: http://clojuredocs.org/clojure_contrib/clojure.contrib.java-utils/file I see this example: (. (clojure.contrib.java-utils/file ...) exists) I'd like to do that but I don't know how with the modern clojure.java.io. I know I can use Java File objects, which has a similar exists method, but I wonder if there is any modern Clojure equivalent? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: thinking in data, polymorphism, etc.
On Thu, Oct 25, 2012 at 1:49 PM, Mark Engelberg mark.engelb...@gmail.com wrote: So my vote is for multimethods, which is at least as clean and fast as manual dispatch with more flexibility. Records/protocols may have some additional performance benefits in the right use cases, but in my experience it definitely comes at a cost. i thought the main problem with multimethods (in most any language that has them) was that it is hard to make sure the dispatches are all exactly what you really want e.g. that you've covered all cases, etc.? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Clojurescript externs when using a local file (cljsbuild)
Can't seem to get the extern functionality to work, or I'm using it wrong.
Basically I have two files: One live and one test. The test file is built
with a separate build definition. I want the test file to be able to see
the live file using the built in namespace functionality.
This is the live project:
{ :id live
:source-path src-cljs/live/
:compiler
{ :output-to resources/public/js/*live*/main.js
:optimizations :simple
:pretty-print true}}
I have the test configuration including the file created above:
{ :id test
:source-path src-cljs/test/
:compiler
{ :output-to resources/public/js/*test*/main.js
:optimizations :simple
:externs [resources/public/js/*live*/main.js]
:pretty-print true}}]}
This is the namespace that I want to include for testing that is in the
live file resources/public/js/*live*/main.js:
(ns helper.webTemplate ...)
This is my attempt to include that namespace in the test file
resources/public/js/*test*/main.js:
(ns helper.webTemplate.test
(:require
[helper.webTemplate :as template]...)
With error:
required helper.webTemplate namespace not provided yet...
Is there a special (Or easier way) to use namespaces in local files? I
could just have the test build move down a level since my folder structure
is:
/src-cljs
/live
/test
But would like to know if I can avoid that.
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Re: (if (io/file path-to-session-file) -- returns false though file exists
The only modern Clojure methods I'm aware of for checking for the existence of a file are the Java method (.exists (io/file filename-string)), or using something like the fs library: https://github.com/Raynes/fs I'm surprised if the if (io/file path-to-session-fie) always returns false in your code example, because (io/file string) returns a Java File object even if there is no such file, and Clojure if evaluates that as true, not false. Andy On Oct 25, 2012, at 3:21 PM, larry google groups wrote: So, again, I'm trying to use Clojure to rebuild a PHP site. Right now I need the Clojure code to read the PHP session files. In the below function, I have a println that shows me that the path points to a file that really does exist. And yet this if() clause seems to always return false. (defn does-session-exist? [session-id] (let [path-to-session-file (str /var/lib/php5/sess_ session-id)] (println path-to-session-file) (if (io/file path-to-session-file) true false))) io is an alias: (:require [clojure.string :as st] [clojure.java.io :as io] [clojure.data.json :as json] [who-is-logged-in.memory_display :as who]) I look here and see that the old monolithic Clojure contrib had an exists function: http://clojuredocs.org/clojure_contrib/clojure.contrib.java-utils/file I see this example: (. (clojure.contrib.java-utils/file ...) exists) I'd like to do that but I don't know how with the modern clojure.java.io. I know I can use Java File objects, which has a similar exists method, but I wonder if there is any modern Clojure equivalent? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: data.json 0.2.0
Thanx Stuart! That looks great, at a glance. On Thu, Oct 25, 2012 at 1:25 PM, Stuart Sierra the.stuart.sie...@gmail.com wrote: I'm sorry for causing people extra work. How's this for a solution: https://github.com/clojure/data.json/commit/6ee71009946731d89ef8f98e7b659fa82443b6a2 This allows the 0.2.x code to pass all the tests for data.json 0.1.3. I can't retract the 0.2.0 release, but if I push this out as 0.2.1 the compatibility issues should be at a minimum. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: what is the modern equivalent of clojure.contrib.java-utils/file?
On Thu, Oct 25, 2012 at 12:52 PM, larry google groups lawrencecloj...@gmail.com wrote: Okay, if I look here: http://clojure.github.com Can I assume that anything that starts with clojure.core is not a dependency? And everything else is? No, some clojure.core.* namespaces are contribs (and need a project.clj dependency), some are built-in. Per my original email: On Thursday, October 25, 2012 2:57:26 PM UTC-4, Sean Corfield wrote: http://clojure.github.com If it's listed separated there, it's a contrib you need to pull in explicitly. Otherwise it's part of Clojure itself. Everything listed in the left hand column is a contrib that you need to pull in (as a dependency) in your project.clj, including: core.cache core.incubator core.match core.memoize core.unify (and core.logic which is, for some reason, missing from that list) Clojure's namespaces are documented here (linked from 'clojure' in the left column of the above page): http://clojure.github.com/clojure/ Anything listed in the left hand column here is built-in (also listed under Table of Contents on the right), no dependency needed (other than Clojure itself), you just need to :require it in your namespace. Finding clojure.core.protocols is a little harder, since it's a sub-namespace of clojure.core so you'll find it here: http://clojure.github.com/clojure/clojure.core-api.html Specifically: http://clojure.github.com/clojure/clojure.core-api.html#clojure.core.protocols You might find the Clojure Atlas helpful for navigating the built-in Clojure namespaces and functions: http://www.clojureatlas.com/ It's a bit of a sprawling universe of namespaces and can be a bit daunting when you first start working in Clojure but you soon get used to the layout (honest!). Hope that helps? -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
let in the middle of thread-first
Let's say I have a set of thread-first calls: (- url a b c d e) And let's say that I need to process and save the result of function b as a second parameter to function e (function b returns a file, and function e needs the extention of that file). How would I drop a let into the middle of the thread calls without making a large mess? The only suggestion I've gotten so far is to move calls A and B into a let before the thread-first so I can process their return values. jason -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
*default-data-reader-fn* has landed!
https://github.com/clojure/clojure/commit/79a1b793f87af417b430450f3c24e7cfe456e3e2 Super exciting! Thanks guys! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: let in the middle of thread-first
I haven't tried them, but you may be in luck for Clojure 1.5. https://github.com/clojure/clojure/commit/026691e2f6cc8d1bab4feb7e577530a9f06fd85e Thanks, Ambrose On Fri, Oct 26, 2012 at 8:24 AM, Jason Bennett jaso...@gmail.com wrote: Let's say I have a set of thread-first calls: (- url a b c d e) And let's say that I need to process and save the result of function b as a second parameter to function e (function b returns a file, and function e needs the extention of that file). How would I drop a let into the middle of the thread calls without making a large mess? The only suggestion I've gotten so far is to move calls A and B into a let before the thread-first so I can process their return values. jason -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: (if (io/file path-to-session-file) -- returns false though file exists
On Thu, Oct 25, 2012 at 3:21 PM, larry google groups lawrencecloj...@gmail.com wrote: I look here and see that the old monolithic Clojure contrib had an exists function: http://clojuredocs.org/clojure_contrib/clojure.contrib.java-utils/file I see this example: (. (clojure.contrib.java-utils/file ...) exists) I'd like to do that but I don't know how with the modern clojure.java.io. That's a Java method invocation, equivalent to (.exists (io/file ...)) with your io alias. -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: let in the middle of thread-first
let- seems to rebind the same name repeatedly, so that probably wouldn't help. You could easily create a macro that bound a new name if it encounters a literal vector in the arguments and evaluated the remaining forms in the context of those bindings: (somevariantof- url a [file b] c d (f (extension file))) Or something like that. On Thu, Oct 25, 2012 at 5:53 PM, Ambrose Bonnaire-Sergeant abonnaireserge...@gmail.com wrote: I haven't tried them, but you may be in luck for Clojure 1.5. https://github.com/clojure/clojure/commit/026691e2f6cc8d1bab4feb7e577530a9f06fd85e Thanks, Ambrose On Fri, Oct 26, 2012 at 8:24 AM, Jason Bennett jaso...@gmail.com wrote: Let's say I have a set of thread-first calls: (- url a b c d e) And let's say that I need to process and save the result of function b as a second parameter to function e (function b returns a file, and function e needs the extention of that file). How would I drop a let into the middle of the thread calls without making a large mess? The only suggestion I've gotten so far is to move calls A and B into a let before the thread-first so I can process their return values. jason -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- Ben Wolfson Human kind has used its intelligence to vary the flavour of drinks, which may be sweet, aromatic, fermented or spirit-based. ... Family and social life also offer numerous other occasions to consume drinks for pleasure. [Larousse, Drink entry] -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
ANN: Guzheng 1.2.5
Guzheng is a library for doing branch coverage analysis on Clojure projects at the command line. Guzheng will warn you which branches were not executed in your project. It understands all forms of conditional execution in clojure.core, except for lazy sequence constructors, macros, protocols, and when-first. All other forms of conditional execution will be flagged if there were never executed while the program ran. To use guzheng, simply add [lein-guzheng 1.4.3] to your leiningen plugins or dependencies (guzheng is compatible with Lein1 and Lein2). Basic usage: lein guzheng my.ns -- test # What code in my.ns wasn't executed by the tests? See https://github.com/dgrnbrg/guzheng/blob/master/lein-guzheng/README.md for more on usage. Pull requests welcome! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: ANN: Guzheng 1.2.5
How does it work? What kinds of dead-code can it detect? Thanks, Ambrose On Fri, Oct 26, 2012 at 9:17 AM, David Greenberg dsg123456...@gmail.comwrote: Guzheng is a library for doing branch coverage analysis on Clojure projects at the command line. Guzheng will warn you which branches were not executed in your project. It understands all forms of conditional execution in clojure.core, except for lazy sequence constructors, macros, protocols, and when-first. All other forms of conditional execution will be flagged if there were never executed while the program ran. To use guzheng, simply add [lein-guzheng 1.4.3] to your leiningen plugins or dependencies (guzheng is compatible with Lein1 and Lein2). Basic usage: lein guzheng my.ns -- test # What code in my.ns wasn't executed by the tests? See https://github.com/dgrnbrg/guzheng/blob/master/lein-guzheng/README.md for more on usage. Pull requests welcome! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: let in the middle of thread-first
On 10/25/12 6:24 PM, Jason Bennett wrote: Let's say I have a set of thread-first calls: (- url a b c d e) And let's say that I need to process and save the result of function b as a second parameter to function e (function b returns a file, and function e needs the extention of that file). How would I drop a let into the middle of the thread calls without making a large mess? The only suggestion I've gotten so far is to move calls A and B into a let before the thread-first so I can process their return values. jason Pallet's thread-exp library has a let- macro that would do the trick: https://github.com/pallet/thread-expr/blob/develop/src/pallet/thread_expr.clj#L100-106 I love the thread-expr library but when I spoke with Hugo Duncan at Clojure West he said that pallet's use of it was largely being replaced by monads. -Ben -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Clojurescript externs when using a local file (cljsbuild)
For what you're trying to do, :externs is not the solution.
Ultimately, all you need to do is make sure that both src-cljs/live and
src-cljs/test are on the classpath at compile time. The easiest way to do
this would be to put both builds into the same project:
:builds
{:live {:source-path src-cljs/live :compiler {...}}
:test {:source-path src-cljs/test :compiler {...}}}
When :builds contains multiple entries, they are all added to the
classpath, and thus helper.webTemplateTest will be able to load
helper.webTemplate.
:externs is used for a totally different purpose (JavaScript interop). If
you want to learn more about that, I recommend reading this:
http://lukevanderhart.com/2011/09/30/using-javascript-and-clojurescript.html
.
-Evan
On Thursday, October 25, 2012 1:25:17 PM UTC-7, Sean S wrote:
Can't seem to get the extern functionality to work, or I'm using it wrong.
Basically I have two files: One live and one test. The test file is built
with a separate build definition. I want the test file to be able to see
the live file using the built in namespace functionality.
This is the live project:
{ :id live
:source-path src-cljs/live/
:compiler
{ :output-to resources/public/js/*live*/main.js
:optimizations :simple
:pretty-print true}}
I have the test configuration including the file created above:
{ :id test
:source-path src-cljs/test/
:compiler
{ :output-to resources/public/js/*test*/main.js
:optimizations :simple
:externs [resources/public/js/*live*/main.js]
:pretty-print true}}]}
This is the namespace that I want to include for testing that is in the
live file resources/public/js/*live*/main.js:
(ns helper.webTemplate ...)
This is my attempt to include that namespace in the test file
resources/public/js/*test*/main.js:
(ns helper.webTemplate.test
(:require
[helper.webTemplate :as template]...)
With error:
required helper.webTemplate namespace not provided yet...
Is there a special (Or easier way) to use namespaces in local files? I
could just have the test build move down a level since my folder structure
is:
/src-cljs
/live
/test
But would like to know if I can avoid that.
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Re: Clojurescript externs when using a local file (cljsbuild)
One other thing I ought to mention is that your *.cljs files need to be arranged in an appropriate directory structure (i.e. the directories must match the namespaces): /src-cljs/live/helper/webTemplate.cljs /src/cljs-test/helper/webTemplate/test.cljs The ClojureScript compiler (sadly) allows files to shirk this convention if they're in the main :source-path (it just grabs ALL *.cljs files recursively). However, if you're loading *.cljs files from a different directory, they will be loaded as Java resources, and thus need to use the Java directory conventions. -Evan -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Generating permutations in core.logic
On Thu, Oct 25, 2012 at 3:10 PM, Jordan Lewis jordanthele...@gmail.comwrote: Hi, I'm new to core.logic and logic programming in general. I tried to write a small program to generate all permutations of any size for an input list with unique elements. To start, I hardcoded the input list to be (range 3). Here's what I came up with: Thanks for this, this actually brought a fairly serious bug to my attention. core.logic 0.8.0-beta2 is being released and should address the distincto issue you encountered. David -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
