Re: Dynamic gen-class
Hi, On Jun 28, 5:38 am, Brian Hurt wrote: > This is actually something that has been bugging me for a while. Most of > the time this isn't a problem (being unable to generate classes in the repl, > basically), except in one case: exceptions. It'd be nice to be able to > define classes that inherit from throwable, and be able to catch them, and > have this code work the same way in the repl and compiled. I'd like to see some unified error handling in Clojure. c.c.error-kit could be an option. Or c.c.condition. Then you wouldn't have to generate a exception class, but could use the pre-delivered Condition augmented with easily accessible meta data. Sincerely Meikel -- 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: Life on the bleeding edge
I ran mvn clean first. -- 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: Life on the bleeding edge
OK, I just tried building clojure-contrib pointing at a clojure.jar
built from the current master branch. I get the same errors (on
Windows). Here are more details:
Testing clojure.contrib.test-io
FAIL in (test-as-url) (run-test9074812622524104689.clj:45)
expected: (= (URL. "file:/foo") (as-url (File. "/foo")))
actual: (not (= # #))
FAIL in (test-relative-path-string) (run-test9074812622524104689.clj:45)
absolute path strings are forbidden
expected: (thrown? IllegalArgumentException (relative-path-string (str File/sepa
rator "baz")))
actual: nil
FAIL in (test-relative-path-string) (run-test9074812622524104689.clj:45)
absolute File paths are forbidden
expected: (thrown? IllegalArgumentException (relative-path-string (File. (str Fi
le/separator "quux"
actual: nil
Testing clojure.contrib.test-profile
FAIL in (test-print-summary) (run-test9074812622524104689.clj:45)
doesn't blow up with no data (assembla #31)
expected: (= "Name mean min max count sum\n" (with-ou
t-str (print-summary {})))
actual: (not (= "Name mean min max count sum\n" "Na
me mean min max count sum\r\n"))
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Re: State of Clojure web development
I am using clojure to rewrite an online bookkeeping application (currently only a test site). I have wanted to learn Lisp and functional programming for a while now. And the emergence of Clojure, and the need to refactor my application, gave me the opportunity. While I'm still new to the language and functional programming, the technical benefits of Clojure were immediately apparent to me. I think others will give a good listing of those technical advantages that Clojure offers. What struck me as I started to use it was how Clojure "feels". Specifically, when I had to redo some Java code in Clojure, it was just striking, the expressive power it gave me over Java. I haven't had this much fun programming since I designed my first language !! Anyways, this isn't a campfire :) The Bookkeeping's current stack is: - Java / Servlets ( I'm going to try Compojure here ) - a custom DSL using http://SableCC.org ( 'proxy' macro beautifully lets me incrementally implement only features I need ) - custom XML Java binding framework ( http://repo.or.cz/w/Bob.git - Clojure negates the need for this ) - A native XML database, eXist, with a RESTful access service Tim On Wed, Jun 23, 2010 at 5:23 PM, James Reeves wrote: > Hello there! > > Chas Emerick's recent "State of Clojure" survey [http://bit.ly/dtdAwb] > indicated that a significant proportion of Clojure users are beginning > to use Clojure for web development. A recent Hacker News posting > [http://bit.ly/91Bu5J] seems to corroborate these results, with > several Clojure-based web applications already out in the wild. > > As one of the main developers of Ring and Compojure, I'd be very > interested to hear more about how people are using Clojure to build > web apps. To this end, I have a few questions I'd like to quiz Clojure > web developers about: > > 1. Have you written, or are you writing, a web application that uses > Clojure? What does it do? > > 2. Which libraries or frameworks are you using? Which versions? > > 3. What made you choose Clojure to develop web applications in? What > are the strengths of Clojure web development? > > 4. What do you think are the current weaknesses of web development in > Clojure? What could be improved? > > 5. Anything else you want to comment on? > > Please reply to this thread with your answers, and thank you very much > in advance for your time. I really appreciate any feedback you can > provide. > > - James > > -- > 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: Life on the bleeding edge
On 28 June 2010 06:11, Garth Sheldon-Coulson wrote: > Ah, thanks. I also see no test failures (archlinux). After realising that the not-AOT-compiled namespaces might still break when require'd, I went ahead and tested a couple of them. There was about a 50/50 split between the working namespaces and the broken namespaces in my (very) small sample. Unfortunately c.c.macro-utils and c.c.pprint are both on the "broken" side, which I guess means no out-of-the-box swanking. :-/ Sincerely, Michał -- 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: Life on the bleeding edge
Ah, thanks. I also see no test failures (archlinux). On Sun, Jun 27, 2010 at 11:31 PM, Michał Marczyk wrote: > On 28 June 2010 05:11, Garth Sheldon-Coulson wrote: > > When I try to compile clojure-contrib with the equiv branch on archlinux, > > maven 2.2.1, jre 1.6.0_20, I get: > > Be sure to run mvn clean first. > > Sincerely, > Michał > > -- > 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: Life on the bleeding edge
On 28 June 2010 05:11, Garth Sheldon-Coulson wrote: > Compiling clojure.contrib.condition.Condition to > /mnt/hgfs/sirfoobar/Documents/Eclipse/clojure-contrib/target/classes > Exception in thread "main" java.lang.NoClassDefFoundError: > clojure/lang/ILookupHost Ah, sorry, it just occurred to me that I might not be checking all the relevant places. After mvn clean, I can build clojure-contrib.jar against equiv clojure.jar, but (require 'clojure.contrib.condition) later throws the above mentioned exception for me at the REPL. Also, I wasn't entirely sure if I'd uploaded the correct jars to the drop the first time round, so I went ahead and uploaded them again. Sincerely, Michał -- 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: Dynamic gen-class
On Sun, Jun 27, 2010 at 4:54 PM, rob levy wrote: > HI Michael, > > If I understand correctly, the proxy function might be what you are looking > for. I think gen-class can only be used with AOT compilation. > > -Rob > > This is actually something that has been bugging me for a while. Most of the time this isn't a problem (being unable to generate classes in the repl, basically), except in one case: exceptions. It'd be nice to be able to define classes that inherit from throwable, and be able to catch them, and have this code work the same way in the repl and compiled. Brian -- 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: Life on the bleeding edge
On 28 June 2010 05:11, Garth Sheldon-Coulson wrote: > When I try to compile clojure-contrib with the equiv branch on archlinux, > maven 2.2.1, jre 1.6.0_20, I get: Be sure to run mvn clean first. Sincerely, Michał -- 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: Life on the bleeding edge
When I try to compile clojure-contrib with the equiv branch on archlinux, maven 2.2.1, jre 1.6.0_20, I get: Compiling clojure.contrib.condition.Condition to /mnt/hgfs/sirfoobar/Documents/Eclipse/clojure-contrib/target/classes Exception in thread "main" java.lang.NoClassDefFoundError: clojure/lang/ILookupHost Everything works fine with master. Not that I expect contrib to work with equiv, but it's curious that it works for Michal and not for me. Garth > Everything works fine for me in an Ubuntu environment. > > -- 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: Life on the bleeding edge
On 28 June 2010 03:23, Mark Engelberg wrote: > Thanks. I had tried that, but I got further as soon as I tried: > mvn package -Dclojure.jar=c:/absolute/path/to/clojure.jar > > I'm now getting 3 failures in clojure.contrib.test_io and 1 in test_profile. > > Is this normal, or is something else going on here, perhaps some > incompatibility between the equiv branch of clojure and the master > branch of clojure-contrib? If it is an incompatibility, what branch > of contrib should I change to, and how do I do it (as I mentioned, I > got an error when I tried "git checkout origin/new")? Everything works fine for me in an Ubuntu environment. Maybe you could try building contrib against a clojure.jar locally built from master, just to check if it's an existing problem with contrib builds on Windows? Also, if you just want to play around with the equiv branch, here are my locally compiled jars: http://drop.io/cljequivjars (Set to expire in a week from now.) Sincerely, Michał -- 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: Life on the bleeding edge
On Sun, Jun 27, 2010 at 5:33 PM, Michał Marczyk wrote: > mvn package -Dclojure.jar=/absolute/path/to/clojure.jar Thanks. I had tried that, but I got further as soon as I tried: mvn package -Dclojure.jar=c:/absolute/path/to/clojure.jar I'm now getting 3 failures in clojure.contrib.test_io and 1 in test_profile. Is this normal, or is something else going on here, perhaps some incompatibility between the equiv branch of clojure and the master branch of clojure-contrib? If it is an incompatibility, what branch of contrib should I change to, and how do I do it (as I mentioned, I got an error when I tried "git checkout origin/new")? -- 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: Life on the bleeding edge
On 28 June 2010 01:53, Mark Engelberg wrote: > Ran ant. Didn't work (no ant build file. Why does clojure-contrib > have a different build process than clojure?). Good question. > Ran "maven package" in the clojure-contrib directory. You need to tell it where to look for clojure.jar. On Linux, this is accomplished as follows: mvn package -Dclojure.jar=/absolute/path/to/clojure.jar Hopefully the Windows command accepts the same option format. Sincerely, Michał -- 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: the joys of lisp
Certainly macros can be dangerous if used recklessly or clumsily, but > isn't trusting the programmer and giving him powerful tools what Lisp > is all about? No other language provides the same power of expression. > A tour through the Clojure code demonstrates just how powerful this > idea is and how easy it makes it for the language implementors to > implement features in a few lines of code that are major bullet-point > features in other languages. > > In my opinion it is much better to empower developers and build a culture of good taste and self-discipline, than to limit the language in an attempt to enforce particular styles. Python is the latter and Lisp is the former. And Python code is often convoluted because of programmers working around the limitations imposed by the language. And don't get me started on lines of code that begin at column 80 etc. ;) I would argue in favor of user-defined reader macros for these same reasons, they are rarely needed but why not maximize the power of Clojure? I think the last word on this from Rich Hickey was "many things that would otherwise have forced people to reader macros may end up in Clojure, where everyone can benefit from a common approach". To me this is Rich being like Guido von Rossum, but maybe there are other good reasons behind the decision that he has either not articulated or I just am not aware of/haven't read. Rob -- 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
Life on the bleeding edge
I spent some time today trying unsuccessfully to get the equiv branch up and running on Windows. I'd appreciate some guidance. I downloaded git, installed git. Used git to "clone" the github repository. Used git to "checkout origin/equiv". Downloaded ant. Installed ant. Ran ant. Seemed to work. Used git to "clone" the clojure-contrib github repository. Ran ant. Didn't work (no ant build file. Why does clojure-contrib have a different build process than clojure?). Installed maven. Ran "maven package" in the clojure-contrib directory. It churned for a while, and the reported a java exception: "Unable to resolve symbol: flatten in this context (literals.clj: 169)" and an enormous stacktrace. I thought maybe the contrib branch is incompatible with this new branch of clojure. So I tried: "git checkout origin/new" but got an error that I can't switch branches due to a local change in test_math.clj (which makes no sense to me because I didn't make any changes to any file after the initial clone). It took me a long time to get this far, but now I feel stuck. Any ideas? -- 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: the joys of lisp
On Jun 27, 1:17 pm, Mike Meyer wrote: > Not quite - it's to keep the language *readable*. And if there's a use > case for a feature that outweighs the damage done by abusing it, > they'll add it. Witness with, list comprehensions, and those > never-to-sufficiently-cursed augmented assignment operators. This > implies simple only to the extent that it shouldn't get so large that > one person can't keep the entire language in their head. Python passed that point for me a long time ago. I'm always referring to the docs. But that's true of most of the languages I work with now. > So how does providing a drill press and bolt set (i.e. - macros) to > the end user fit into this? Certainly macros can be dangerous if used recklessly or clumsily, but isn't trusting the programmer and giving him powerful tools what Lisp is all about? No other language provides the same power of expression. A tour through the Clojure code demonstrates just how powerful this idea is and how easy it makes it for the language implementors to implement features in a few lines of code that are major bullet-point features in other languages. > Well, there are already multiple OO implementations on top of > 1.1. Most of them are more to show that you can do that if you really > want to, and I'm not sure how much the additions to 1.2 will obsolete > them. I have to admit it's not entirely clear to me how to reconcile java objects, tagged hashes, and protocols as alternative OO models in Clojure It's probably just a lack of effort on my part in reading the source and docs but I can't say that the ADT/OO story in Clojure is as simple as the Python/Ruby approach, at least from the point of view of the beginner. -- 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: Dynamic gen-class
HI Michael, If I understand correctly, the proxy function might be what you are looking for. I think gen-class can only be used with AOT compilation. -Rob On Sun, Jun 27, 2010 at 8:19 AM, Michael Jaaka wrote: > Hi, > > Is there any way to generate class in runtime and then use it? > How far I can only generate interfaces. > > This works: > > (do > (gen-interface :name test.commons.Me >:methods [[ me [ String ] void ]]) > > (def z (reify test.commons.Me >(me [t z] (println "hello world" z > > (.me z "wowo") > ) > > > > That doesn't: > > > > (do > (gen-class :name test.commons.Mee >:state sema >:methods [ >[ me2 [ String ] void ]] >:prefix "mee-" > ) > > (defn mee-me2[ this a ] >(println "hello" a "had state" (.sema this))) > > (.me2 (test.commons.Mee. ) "world") > ) > > > > -- > 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: the joys of lisp
On Sun, 27 Jun 2010 12:41:36 -0700 (PDT) cageface wrote: > Python definitely seems to be the product of a very different design > philosophy than Lisp. I've always felt it was too prescriptive. > Omitting features that *might* be misused in an effort to keep the > language simple seems to have backfired on them. Not quite - it's to keep the language *readable*. And if there's a use case for a feature that outweighs the damage done by abusing it, they'll add it. Witness with, list comprehensions, and those never-to-sufficiently-cursed augmented assignment operators. This implies simple only to the extent that it shouldn't get so large that one person can't keep the entire language in their head. And yes, it's gotten a bit larger than most people would like. But that's part of the point of Python 3.0 - removing some of the bits that have been obsoleted by more recent additions, or at least moving them out of the language core. > Too keep up with the > competition they've had to add so many new features to the core > language (list comprehensions, annotations, iterators, with statement, > properties etc) that Python doesn't feel like a small, simple language > to me at all anymore. Anyway, I don't mean to pick on Python because > it's not a bad language. I think this just illustrates that it's > better to build from a simple, flexible core than to bolt on pieces > later. So how does providing a drill press and bolt set (i.e. - macros) to the end user fit into this? > I think you can go too far in the other direction too though. > Certainly Scheme is a very elegant language but omits so much from the > spec that you have dozens of incompatible OO implementations floating > around. I think at a minimum a language should provide a single, > consistent, standard implementation of the following: > > 1. a string/text type > 2. an abstract datatype/object model > 3. container types > 4. concurrency primitives > 5. ffi > > Clojure covers these points well, I think, and I'm not worried about > Clojure fracturing into a babel of incompatible macro-based dialects. Well, there are already multiple OO implementations on top of 1.1. Most of them are more to show that you can do that if you really want to, and I'm not sure how much the additions to 1.2 will obsolete them. http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org -- 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: the joys of lisp
Python definitely seems to be the product of a very different design philosophy than Lisp. I've always felt it was too prescriptive. Omitting features that *might* be misused in an effort to keep the language simple seems to have backfired on them. Too keep up with the competition they've had to add so many new features to the core language (list comprehensions, annotations, iterators, with statement, properties etc) that Python doesn't feel like a small, simple language to me at all anymore. Anyway, I don't mean to pick on Python because it's not a bad language. I think this just illustrates that it's better to build from a simple, flexible core than to bolt on pieces later. I think you can go too far in the other direction too though. Certainly Scheme is a very elegant language but omits so much from the spec that you have dozens of incompatible OO implementations floating around. I think at a minimum a language should provide a single, consistent, standard implementation of the following: 1. a string/text type 2. an abstract datatype/object model 3. container types 4. concurrency primitives 5. ffi Clojure covers these points well, I think, and I'm not worried about Clojure fracturing into a babel of incompatible macro-based dialects. -- 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: State of Clojure web development
At Akamai we are using Clojure combined with Compojure for a project that involves the live transcoding of mobile content. I can't talk about the details, nor mention any specific libraries or features we are using, except to say that we chose Clojure for the normal reasons: its meta-programming and concurrency features. We are very happy with our decision to use Clojure. (We're hiring for this project.) Jeffrey Straszheim Senior Software Engineer -- 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 <><><> Office: 954.652.2243 Cell: 561.504.9913 Akamai Technologies 8 Cambridge Center Cambridge, MA 02142 <> On Jun 23, 2010, at 5:23 PM, James Reeves wrote: > Hello there! > > Chas Emerick's recent "State of Clojure" survey [http://bit.ly/dtdAwb] > indicated that a significant proportion of Clojure users are beginning > to use Clojure for web development. A recent Hacker News posting > [http://bit.ly/91Bu5J] seems to corroborate these results, with > several Clojure-based web applications already out in the wild. > > As one of the main developers of Ring and Compojure, I'd be very > interested to hear more about how people are using Clojure to build > web apps. To this end, I have a few questions I'd like to quiz Clojure > web developers about: > > 1. Have you written, or are you writing, a web application that uses > Clojure? What does it do? > > 2. Which libraries or frameworks are you using? Which versions? > > 3. What made you choose Clojure to develop web applications in? What > are the strengths of Clojure web development? > > 4. What do you think are the current weaknesses of web development in > Clojure? What could be improved? > > 5. Anything else you want to comment on? > > Please reply to this thread with your answers, and thank you very much > in advance for your time. I really appreciate any feedback you can > provide. > > - James >
Re: the joys of lisp
On Sun, 27 Jun 2010 11:58:16 -0700 (PDT) cageface wrote: > When I read about new "features" in other languages that would be > simple macros in Lisp I just have to smile: > http://docs.python.org/dev/reference/compound_stmts.html#with Many in the Python community consider this an advantage of Python. It means semantic changes only get added to the language after proper consideration by the community, the experts who maintain the language, and the BDFL. Common LISP (or more accurately, the evolution from LISP 1.5 through the many and sundry dialects and thence to Common LISP) is held up as an example of how badly wrong allowing anyone to create statements can go. But yeah, many people in the Python community also want LISP-like macros, extolling the virtues of "with" so often that it was added to the language. And a nice addition it was (seems kinda old these days...). http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org -- 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
the joys of lisp
When I read about new "features" in other languages that would be simple macros in Lisp I just have to smile: http://docs.python.org/dev/reference/compound_stmts.html#with -- 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: Drawable Sets
>
> I think you can solve the holes on delete by permuting the removed element
> with the last element and keeping a map from value to their index.
>
Good idea!
Thanks you very much for these suggestions.
>
You're welcome. The hashtrie is a much better idea for this situation, of
course.
Couldn't you just slightly extend Rich's PersistentHashMap? (Maybe I'm
misunderstanding what you're looking for or what PersistentHashMap is all
about.)
Just brainstorming now:
If you did extend Rich's, it would be pretty cool to build a generalized
version of Clojure's hash-map construction function ("hash-map-searchable"
or something) that took two extra arguments: a function called by a leaf
node on its value and a function called by a non-leaf node on a coll of its
subnodes. On every update, every node in the update path would call one of
these functions and store the result in the node.
(If your objects are maps with key :mass, then the first function would be
:mass, and the second function would be #(reduce + %).)
Then one could build a general function "search-map" taking a hash-map and a
search function. The search function would accept a coll of stored node
values (the values of a node's subnodes) and return the index of the subnode
to follow down the tree. The search function would be called on the root
node on down, following the returned index each time, until it hit a leaf
node, which it would return. You could implement your case really easily in
this framework, I think, and it might also make it easy to build other kinds
of more complicated search down the branches of a hash-map hashtrie.
Garth
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Re: New Primitive data types (equal branch) - impact on optimized code.
On Sat, Jun 26, 2010 at 6:56 PM, j-g-faustus wrote: > > On my machine this is about 4x slower than the shootout Java > implementation. Using Java as the baseline and comparing my local > results to the shootout timings, it puts Clojure 1.1 on par with > Erlang, Go and OCaml. > > On profiling I have a bunch of intCast(Object) and doubleCast(double) > totaling ~9% CPU time (no screenshot yet, sorry), I'll see if I can > eliminate them for a few percent improvement. > Which Hotspot and flags do you use? You could be more idiomatic and probably faster with 1.2's (definterface Body-ish (x[]..). x= ...) and the like with type annotations (or better with protocols, but they have no annotations yet, I think) and (deftype Body [x y ...] Body-ish ). Object field access are a bit faster than array access on the jvm. (as a first try, you could mesure the difference with using the Body class from java and the main loop in clojure, to check where the difference comes from) Best regards, Nicolas. -- 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: Protocols
On Jun 27, 2010, at 1:09 AM, Mark Engelberg wrote: Is there a list somewhere of all the protocols built-in to Clojure 1.2's core that are available for extension? There are no extension points built on protocols in Clojure yet. Delivering protocols is step one, re-architecting the core abstractions in terms of protocols is still to come. Rich -- 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: Converting list to Map
On Sat, 26 Jun 2010 15:54:34 -0700 (PDT) hsarvell wrote: > I tried to find something in core / on Google to do this but didn't, > here is what I have anyway: > > (defn lst-to-map [lst] >(reduce > (fn [hsh chunk] > (assoc hsh (first chunk) (last chunk))) > (hash-map) > (partition 2 lst))) > > Is there an easier/shorter way? (apply hash-map lst) http://www.mired.org/consulting.html Independent Network/Unix/Perforce consultant, email for more information. O< ascii ribbon campaign - stop html mail - www.asciiribbon.org -- 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: Enhanced primitive support - redux
If there is some sort of new numeric tower on the plate, what would be some desirable properties? On Jun 25, 10:58 pm, Andrzej wrote: > On Sat, Jun 26, 2010 at 4:04 AM, Rich Hickey wrote: > > equiv, the revenge of num > > Has it already been decided that some sort of this new numeric tower > will find its way into Clojure? > > Andrzej -- 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
Question: pmap + number of threads + number of cpus
(running clojure 1.2 snapshot)
Q1: Why does pmap use the number of available processors + 2? I would
have thought it would just use the number of avail processors...
Q2: Could someone clear up my misunderstanding of pmap w/ respect to
the code snippets below? Pmap doesn't seem to be limiting the number
of threads to the number of processors + 2...
I've created an anon func that does't return, so I wouldn't expect the
pmap step function to advance beyond 4 (I have 2 processors):
#1: Limit pmap to # of processors
--
user=> (pmap #(while true (do (println "Thread: " (.getId (Thread/
currentThread)) "item: " %)(Thread/sleep 500))) (range
(.availableProcessors (Runtime/getRuntime
Thread: 12 item: 0
(Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
--> just two threads running, as expected
#2: Limit pmap to # of processors * 10
--
user=> (pmap #(while true (do (println "Thread: " (.getId (Thread/
currentThread)) "item: " %)(Thread/sleep 500))) (range (* 10
(.availableProcessors (Runtime/getRuntime)
Thread: Thread: 12 item: 0
(Thread: 25 item: 13
Thread: 24 item: 12
Thread: 23 item: 11
Thread: 22 item: 10
Thread: 21 item: 9
Thread: 20 item: 8
Thread: 19 item: 7
Thread: 18 item: 6
Thread: 17 item: 5
Thread: 16 item: 4
Thread: 15 item: 3
--> In this short snippet, you can see > 4 threads running...expected?
toddg=> (source pmap)
(defn pmap
"Like map, except f is applied in parallel. Semi-lazy in that the
parallel computation stays ahead of the consumption, but doesn't
realize the entire result unless required. Only useful for
computationally intensive functions where the time of f dominates
the coordination overhead."
{:added "1.0"}
([f coll]
(let [n (+ 2 (.. Runtime getRuntime availableProcessors))
rets (map #(future (f %)) coll)
step (fn step [[x & xs :as vs] fs]
(lazy-seq
(if-let [s (seq fs)]
(cons (deref x) (step xs (rest s)))
(map deref vs]
(step rets (drop n rets
-Todd
p.s. It seems that any email I send from my desktop client
(thunderbird) does not reach the clojure alias
(clojure@googlegroups.com). Only emails that I send from the
groups.google.com web page seem to make it to the list. I've sent
several thank-you to folks who have responded to me in the past, so I
apologize if these did not materialize.
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Converting list to Map
I tried to find something in core / on Google to do this but didn't, here is what I have anyway: (defn lst-to-map [lst] (reduce (fn [hsh chunk] (assoc hsh (first chunk) (last chunk))) (hash-map) (partition 2 lst))) Is there an easier/shorter way? -- 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
Question re: pmap and the number of available processors
(running clojure 1.2 snapshot)
Q1: Why does pmap use the number of available processors + 2? I would
have thought it would just use the number of avail processors...
Q2: Could someone clear up my misunderstanding of pmap w/ respect to the
code snippets below? Pmap doesn't seem to be limiting the number of
threads to the number of processors + 2...
I've created an anon func that does't return, so I wouldn't expect the
pmap step function to advance beyond 4 (I have 2 processors):
#1: Limit pmap to # of processors
--
user=> (pmap #(while true (do (println "Thread: " (.getId
(Thread/currentThread)) "item: " %)(Thread/sleep 500))) (range
(.availableProcessors (Runtime/getRuntime
Thread: 12 item: 0
(Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
Thread: 13 item: 1
Thread: 12 item: 0
--> just two threads running, as expected
#2: Limit pmap to # of processors * 10
--
user=> (pmap #(while true (do (println "Thread: " (.getId
(Thread/currentThread)) "item: " %)(Thread/sleep 500))) (range (* 10
(.availableProcessors (Runtime/getRuntime)
Thread: Thread: 12 item: 0
(Thread: 25 item: 13
Thread: 24 item: 12
Thread: 23 item: 11
Thread: 22 item: 10
Thread: 21 item: 9
Thread: 20 item: 8
Thread: 19 item: 7
Thread: 18 item: 6
Thread: 17 item: 5
Thread: 16 item: 4
Thread: 15 item: 3
--> In this short snippet, you can see > 4 threads running...expected?
toddg=> (source pmap)
(defn pmap
"Like map, except f is applied in parallel. Semi-lazy in that the
parallel computation stays ahead of the consumption, but doesn't
realize the entire result unless required. Only useful for
computationally intensive functions where the time of f dominates
the coordination overhead."
{:added "1.0"}
([f coll]
(let [n (+ 2 (.. Runtime getRuntime availableProcessors))
rets (map #(future (f %)) coll)
step (fn step [[x & xs :as vs] fs]
(lazy-seq
(if-let [s (seq fs)]
(cons (deref x) (step xs (rest s)))
(map deref vs]
(step rets (drop n rets
-Todd
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Re: New Primitive data types (equal branch) - impact on optimized code.
Possibly of interest here, although I've only tested it using Clojure 1.1: I just did an implementation of the n-body problem from http://shootout.alioth.debian.org/u32q/benchmark.php?test=nbody&lang=all The fastest code I've managed so far is here: http://github.com/j-g-faustus/Clojure-test-code/blob/master/shootout/nbody.clj On my machine this is about 4x slower than the shootout Java implementation. Using Java as the baseline and comparing my local results to the shootout timings, it puts Clojure 1.1 on par with Erlang, Go and OCaml. On profiling I have a bunch of intCast(Object) and doubleCast(double) totaling ~9% CPU time (no screenshot yet, sorry), I'll see if I can eliminate them for a few percent improvement. A bit more here: http://stackoverflow.com/questions/3124344/clojure-number-crunching-performance where I am also asking * are there any obvious improvements to my code? * do you consider 4x slower than Java and 10x quicker than Python/Ruby representative for Clojure performance? For the record, I think an order of magnitude quicker than Perl/Python/ Ruby is a quite decent result. ~4x slower than C, Java and Scala is a performance hit I can live with in return for a more comfortable language. If 1.2 gives even better performance, or similar performance with less effort, so much the better. Regards jf PS: If there are no obvious improvements, I'd like to submit this n- body implementation to the shootout. Any objections? (Like "wait for 1.2"?) On Jun 24, 11:08 pm, "Heinz N. Gies" wrote: > The benchmark I did was the fannkuchen-redux benchmark the code I came up > with was the following: > > http://github.com/Licenser/clj-shootout/blob/master/fannkuchen/src/pr... > > the scala version I used is from the alioth shootout: > > http://github.com/Licenser/clj-shootout/blob/master/fannkuchen/scala/... -- 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: Clojure Futures Docs and Functionality
Sounds good to me. The first version of that function I wrote without
returning nil, but just bubbling up the exception. I changed it because I
couldn't think of another area of the Clojure core that threw an exception
like that. Looking through some of the agents code, I think there are some
similar scenarios that do throw an exception.
As far as the seconds/minutes etc stuff. I just added that to not lose
anything from the Java API. Getting rid of that, the much simpler function
looks like:
(defn future-await
"Returns the value of the future just like a deref. If the future has not
completed by timeout, nil is returned"
[^java.util.concurrent.Future f timeout-in-millis]
(.get f timeout-in-millis java.util.concurrent.TimeUnit/MILLISECONDS))
Usage is same as before:
(def fut
(future
(Thread/sleep 1)
"done"))
(future-await fut 1) ; throws java.util.concurrent.TimeoutException
(def fut
(future
(Thread/sleep 1)
"done"))
(future-await fut 10) ; "done"
-Ryan
On Sat, Jun 26, 2010 at 12:56 AM, Meikel Brandmeyer wrote:
> Hi,
>
> Am 25.06.2010 um 20:48 schrieb Daniel Werner:
>
> > On 25 June 2010 05:27, Ryan Senior wrote:
> >> (future-await fut2 2 :minutes) ; => "done"
> >
> > What do others think?
>
> I agree – in particular for point 2.
>
> For point 1: I think "2 :minutes" is not very clojure-like. It sound more
> like Ruby: 2.minutes. A more clojure-like approach would be to an use
> optional keyword argument.
>
> (defn future-await
> [fut & {:keys [timeout]}]
> )
>
> (future-await zukunft)
> (future-await zukunft :timeout time-out-in-ms)
>
> Or of course the simple two-arg-version.
>
> Sincerely
> Meikel
>
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Re: Duplicate key bug in hash-maps
Easy to explain - absolutely, consistent - mm, not really...
I found this new behavior a bit confusing, imo it breaks principle of
least surprise.
This feature is uncommon in dynamic languages (even Scala allows
duplicate keys - Set('a,'a)/Map('a->1,'a->1)).
Also, from the practical point of view, when prototyping:
- repl: user>(some-fn #{1 ...}) ;just experiment here
- file: #{"http://xyz"; ...} ;bunch of statistical data
In both cases occasional duplicate is not critical.
However, one will be forced to spend extra time on input double-check
and/or deal with error message(s).
-anton
On Jun 25, 5:31 pm, Stuart Halloway wrote:
> Duplicate keys in maps/sets are disallowed in literals and factory functions,
> where data is generally literal & inline and therefore likely represents
> coder error:
>
> ; all disallowed
> #{:a :a}
> {:a 1 :a 2}
> (hash-map :a 1 :a 2)
> (hash-set :a :a)
>
> They are allowed in other contexts, where the data could come from anywhere:
>
> ; dumb, but these forms not generally called with a literal
> (set [:a :a])
> (into #{} [:a :a])
>
> I find this behavior consistent and easy to explain, but I was involved in
> the design conversation so maybe I have participant blindness. :-)
>
> Stu
>
>
>
> > On Fri, 25 Jun 2010 15:36:31 +0200
> > Michael Wood wrote:
>
> >> On 25 June 2010 12:27, Tim Robinson wrote:
> >>> I tried Clojure via Githhub today.
>
> >>> Anyone notice this bug that hadn't existed in Version 1.1
>
> >>> user=> #{:item1 {:a "A" :b "B"} :item2 {:a "A" :b "B"}}
> >>> java.lang.IllegalArgumentException: Duplicate key: {:a "A", :b "B"}
>
> >> You're trying to put duplicate values into a set.
>
> > So? Most places, putting a value that's already in a set into the set
> > is a nop. Even in clojure that exhibits the above behavior:
>
> > user=> #{:a :a}
> > java.lang.IllegalArgumentException: Duplicate key: :a
> > user=> (set [:a :a])
> > #{:a}
> > user=> (conj #{:a} :a)
> > #{:a}
> > user=>
>
> > Apparently, duplicate keys in sets are only disallowed in set
> > literals. Arguably, that must be a mistake on the users part, but
> > it sure seems to clash with the behavior of sets elsewhere.
>
> > > --
> > Mike Meyer
> > http://www.mired.org/consulting.html
> > Independent Network/Unix/Perforce consultant, email for more information.
>
> > O< ascii ribbon campaign - stop html mail -www.asciiribbon.org
>
> > --
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Re: Duplicate key bug in hash-maps
I agree that duplicate keys in literals are probably a coder error but
IMO this deserves some kind of compiler warning rather than an error.
You're going to get into lots of sticky situations otherwise that only
confuse people if the semantics are different between literals and
other usage. Simple is good.
On Jun 25, 3:31 pm, Stuart Halloway wrote:
> Duplicate keys in maps/sets are disallowed in literals and factory functions,
> where data is generally literal & inline and therefore likely represents
> coder error:
>
> ; all disallowed
> #{:a :a}
> {:a 1 :a 2}
> (hash-map :a 1 :a 2)
> (hash-set :a :a)
>
> They are allowed in other contexts, where the data could come from anywhere:
>
> ; dumb, but these forms not generally called with a literal
> (set [:a :a])
> (into #{} [:a :a])
>
> I find this behavior consistent and easy to explain, but I was involved in
> the design conversation so maybe I have participant blindness. :-)
>
> Stu
>
>
>
> > On Fri, 25 Jun 2010 15:36:31 +0200
> > Michael Wood wrote:
>
> >> On 25 June 2010 12:27, Tim Robinson wrote:
> >>> I tried Clojure via Githhub today.
>
> >>> Anyone notice this bug that hadn't existed in Version 1.1
>
> >>> user=> #{:item1 {:a "A" :b "B"} :item2 {:a "A" :b "B"}}
> >>> java.lang.IllegalArgumentException: Duplicate key: {:a "A", :b "B"}
>
> >> You're trying to put duplicate values into a set.
>
> > So? Most places, putting a value that's already in a set into the set
> > is a nop. Even in clojure that exhibits the above behavior:
>
> > user=> #{:a :a}
> > java.lang.IllegalArgumentException: Duplicate key: :a
> > user=> (set [:a :a])
> > #{:a}
> > user=> (conj #{:a} :a)
> > #{:a}
> > user=>
>
> > Apparently, duplicate keys in sets are only disallowed in set
> > literals. Arguably, that must be a mistake on the users part, but
> > it sure seems to clash with the behavior of sets elsewhere.
>
> > > --
> > Mike Meyer
> > http://www.mired.org/consulting.html
> > Independent Network/Unix/Perforce consultant, email for more information.
>
> > O< ascii ribbon campaign - stop html mail -www.asciiribbon.org
>
> > --
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Re: How does contains? work?
Thank you very much to all for comprehensive explanations. As newcomer to Clojure dare to remark that this is not very consistent semantics of "contains" :) On 25 июн, 21:25, ataggart wrote: > My sense from reading Rich's writing on the subject is that 'contains? > was named with the use of sets in mind. There is also a pairing logic > involved whereby if 'contains? returns true, the the value returned by > 'get is valid (this covers cases in maps where the value actually is > nil). > > As Meikel indicated, this is a well-worn path of discussion and isn't > going to change. > > On Jun 25, 5:15 am, Peter Schuller > wrote: > > > > > > Explain me this, please: > > > > user=> (def x (cons 'a nil)) > > > #'user/x > > > user=> x > > > (a) > > > user=> (contains? x 'a) > > > false > > > user=> > > > contains? checks whether the collection contains the *key*, not the > > value. So for example the list [:a :b] contains keys 0 and 1, but not > > 2 or :a: > > > user=> (contains? [:a :b] 0) > > true > > user=> (contains? [:a :b] 1) > > true > > user=> (contains? [:a :b] 2) > > false > > user=> (contains? [:a :b] :a) > > false > > > That said, it was not obvious from (doc contains?) to me what the > > semantics were for operating on lists. Checking PersistentList, it > > seems contains() always returns false - which makes sense if you > > consider that lists are not functions of indexes (while vectors and > > java arrays are). > > > -- > > / Peter Schuller -- 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: Enhanced primitive support - redux
Thirded. On Jun 25, 4:55 pm, Mark Engelberg wrote: > On Fri, Jun 25, 2010 at 2:39 PM, Garth Sheldon-Coulson wrote: > > Personally, I think (= 3 3M) => true and (= 3/10 0.3M) => true would be nice > > to have, given that (= 3 3N) => true. Both are currently false in equiv. I > > also think (= 3.0M 3.00M) => true would be nice. As Rich said, there's no > > particular reason to have Clojure = work exactly like Java .equals(). I > > think all it would take is a call to .stripTrailingZeros() on each = > > comparison of a BigDecimal. > > Yeah, if it's technically feasible, this definitely makes the most > mathematical sense. -- 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: Duplicate key bug in hash-maps
Can I change the title to:
"Duplicate key error handling feature in hash-sets" ?
I was using the '#' thinking it was short for a hash-map, rather than
a hash-set.
Clojure has more data structures available than I'm used to working
with.
So thanks for the error handling.
Tim
On Jun 25, 9:37 am, Stuart Halloway wrote:
> I think there are two important considerations in favor of how it works now:
>
> (1) The "common case" presumptions (which admittedly may need to be learned).
>
> (2) The need for both flavors. If there wasn't a flavor that rejected
> duplicate keys, somebody would surely ask for it.
>
> Add to these considerations the names of the functions already in play, and
> you get the implementation you see.
>
>
>
> > On Fri, 25 Jun 2010 10:31:57 -0400
> > Stuart Halloway wrote:
>
> >> Duplicate keys in maps/sets are disallowed in literals and factory
> >> functions, where data is generally literal & inline and therefore likely
> >> represents coder error:
>
> >> ; all disallowed
> >> #{:a :a}
> >> {:a 1 :a 2}
> >> (hash-map :a 1 :a 2)
> >> (hash-set :a :a)
>
> > Maps I can see being an error - you lose data in the process.
>
> > However, since you can plug variables of unknown provenance into
> > either the constructor or the literal, that's liable to create a nasty
> > surprise for someone at some point.
>
> > user=> (def a :a)
> > #'user/b
> > user=> (def b :a)
> > #'user/b
> > user=> (hash-set a b)
> > java.lang.IllegalArgumentException: Duplicate key: :a (NO_SOURCE_FILE:6)
> > user=> #{a b}
> > java.lang.IllegalArgumentException: Duplicate key: :a (NO_SOURCE_FILE:0)
> > user=>
>
> >> They are allowed in other contexts, where the data could come from
> >> anywhere:
>
> > It could come from anywhere in the two "forbidden" contexts as well.
>
> >> ; dumb, but these forms not generally called with a literal
> >> (set [:a :a])
> >> (into #{} [:a :a])
>
> >> I find this behavior consistent and easy to explain, but I was involved in
> >> the design conversation so maybe I have participant blindness. :-)
>
> > My initial reaction was "that's a bit odd, but probably a good idea."
> > However, given that I can use variables inside the literal and
> > constructor, I'm leaning the other way.
>
> > Or is (set [a b c]) idiomatic usage in this case, and (hash-set a b c)
> > or #{a b c} to be avoided?
>
> > > --
> > Mike Meyer
> > http://www.mired.org/consulting.html
> > Independent Network/Unix/Perforce consultant, email for more information.
>
> > O< ascii ribbon campaign - stop html mail -www.asciiribbon.org
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Dynamic gen-class
Hi, Is there any way to generate class in runtime and then use it? How far I can only generate interfaces. This works: (do (gen-interface :name test.commons.Me :methods [[ me [ String ] void ]]) (def z (reify test.commons.Me (me [t z] (println "hello world" z (.me z "wowo") ) That doesn't: (do (gen-class :name test.commons.Mee :state sema :methods [ [ me2 [ String ] void ]] :prefix "mee-" ) (defn mee-me2[ this a ] (println "hello" a "had state" (.sema this))) (.me2 (test.commons.Mee. ) "world") ) -- 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: Drawable Sets
That's a super cool idea, but my data have no similar size. Anyway, that's both simple and always better than what I do.(At worst it has an expected complexity of O(n) if all the mass is in one value and the n-1 are zero-ish). I think you can solve the holes on delete by permuting the removed element with the last element and keeping a map from value to their index. Thanks you very much for these suggestions. On Sat, Jun 26, 2010 at 10:04 PM, Garth Sheldon-Coulson wrote: > Well, my idea involves rejection sampling. In order to sample an element > from the set in a mass-weighted fashion, you can sample an element in a > uniform fashion and then reject the sample with a certain probability (more > below). If you do reject the sample, you keep drawing from the uniform > proposal distribution until you get an acceptance. This can be quite > efficient if the most massive element in the set is not too much more > massive than the majority of the other elements. If, however, the elements > have very different masses, then it can be inefficient. Regardless, my > intuition is that you can't do better than rejection sampling in this case, > because the probability distribution from which you're sampling is > constantly changing and not of any particular functional form. -- 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: Drawable Sets
That more or less what I had in mind, but I was wondering if someone has already an Open Sourced code for HashTries in Clojure. But I can try your idea with binary tree first. It seems simpler. Thanks again, Nicolas On Sun, Jun 27, 2010 at 5:13 AM, Jules wrote: > > You can use the same idea for hash tries, just maintain the total > weight in each node and draw with this algorithm. > -- 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
RAM for a Ring app
Approximately how much RAM is required to deploy a small Ring app on 64-bit Ubuntu? -- 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
