Re: question regarding macro (ab)usage
Hi,
I'm not sure my solution is 100% idiomatic, but has some advantages.
General strategy: minimise macro usage. Macros are cool, but
overrated. Put as much as possible into functions. This has several
advantages like easier testing, less macro trap doors, better
readability (no # all over the place) or possibility of hotfixing of
eg. the cleanup code in with-context[1], etc.
So my plan is: put everything in special global variables. Expose them
as options for the functions. The defaults refer to the global
variables which are set with binding. So allows for usage pattern, but
could also allow for easy testing.
(with-context [:some option]
(init-source "bla" :some "option"))
or
(init-source "bla" :some "option" :context manually-crafted-context)
Here is my try:
(declare *context* *thread* *receivers* *sources*)
(defn init-receiver
[topic & {:keys [context receivers]
:or {context *content* receivers *receivers*}
:as options}]
...boring java stuff)
(defn init-source
[topic & {:keys [context sources]
:or {context *content* sources *sources*}
:as options}]
...boring java stuff)
(defn publish
[topic message & {:keys [context sources]
:or {context *content* sources *sources*}
:as options}]
...boring java stuff)
(defn receive
[topic func & {:keys [context receivers]
:or {context *content* receivers *receivers*}
:as options}]
...boring java stuff)
(defn with-context*
[options thunk]
(let [context (create-context options)
thread(create-thread context)
sources (atom {})
receivers (atom {})]
(binding [*context* context
*thread*thread
*sources* sources
*receivers* receivers]
(try
(thunk)
(finally
... close stuff, cleanup)
(defmacro with-context
[options & body]
`(with-context* ~options (fn [] ~...@body)))
Icying (not tested though, but some quick macroexpands seem to be
promising):
(defmacro defsugaredfn
[fnname & fntail]
(let [[docstring fntail] (let [[docstring & tail :as fntail] fntail]
(if (string? docstring)
[docstring tail]
[nil fntail]))
[metamap fntail] (let [[metamap & tail :as fntail] fntail]
(if (map? metamap)
[metamap tail]
[nil fntail]))
args (first fntail)
fntail (next fntail)
options(peek args)
options(when (map? options) options)
mod-options(merge-with into
`{:keys [~'context
~'receivers
~'sources]
:or {~'context *context*
~'receivers
*receivers*
~'sources *sources*}
:as ~'options}
options)
args (if options
(pop args)
(conj args '&))
args (conj args mod-options)]
`(defn ~fnname
~@(concat (when docstring [docstring])
(when metamap [metamap])
[args])
~...@fntail)))
Use as:
(defsugaredfn init-receiver
"with docstring! yeah!"
[topic & {:keys [some] :or {some "option"}}]
...boring java stuff)
or
(defsugaredfn init-receiver
[topic]
...boring java stuff)
context, receivers, source and options will be captured this way and
available in the "boring java stuff" part. Another downside: you have
to take care when you cross thread boundaries. Then you have to use
bound-fn or pass the context and friend explicitely.
(with-context [:some "option"]
...
(bound-fn [] (init-receiver "in another thread"))
...
(fn [] (init-receiver "in another thread" :context
context :receivers receivers)
,...
)
Hope that helps.
Sincerely
Meikel
[1]: With a macro the client code has to be recompiled.
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Re: How often do you use REPL?
cake (http://github.com/ninjudd/cake) has the "tab completion" feature. Because this is very useful, I wonder if this feature should be added to leiningen or Clojure itself. -- 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 regarding macro (ab)usage
hi,
apologies if this is a long question, i would appreciate some guidance here.
i am creating a clojure wrapper around a rather verbose low latency
messaging framework. the main things you can do are publish messages,
receive messages, initialize sources and receivers etc. all are done
through a 'context'. i have ended up with this (silly example):
(with-context [:some "parameter"]
(init-receiver "some-topic" :some "option")
(init-source "some-topic" :on-disconnect #(println "client disconnected"))
(publish "some-topic" "some-message" :other "option")
(receive "some-topic"
(fn [o m] (println "received: " (.dataString m)
which i am fairly happy with. it is all wrapping up access to
underlying java objects (eg a context object, lists of sources,
receivers, threads and so on).
the implementation (somewhat simplified for clarity) is like:
;; these will be bound later
(def init-receiver nil)
(def init-source nil)
(def publish nil)
(def receive nil)
;; real impls with more args than i want to have to pass around
(defn init-receiver-on [context receivers topic] ...boring java stuff)
(defn init-source-on [context sources topic] ...boring java stuff)
(defn publish-on [context sources topic message] ...boring java stuff)
(defn receive-on [context receivers topic func] ...boring java stuff)
(defmacro with-context [options & body]
`(let [context# (create-context options)
thread# (create-thread context)
sources# (atom {})
receivers# (atom {})]
(binding [init-receiver (partial init-receiver-on context# receivers#)
init-source (partial init-source-on context# sources#)
publish (partial publish-on context# sources#)
receiver (partial receive-on context# receivers#)]
(try
(do ~...@body)
(finally
... close stuff, cleanup)
so i am binding those functions to partial applications which use the
lexically scoped context, thread etc when you use the macro. is this
reasonable?
a prior implementation i had was like:
(defmacro with-context [options & body]
`(let [context# (create-context options)
thread# (create-thread context#)]
sources# (atom {})
receivers# (atom {})]
(letfn [(~'publish [topic# msg# & options#] (publish-on context#
sources# topic# msg# options#))
(~'receive [topic# callback# & options#] (receive-on
context# receivers# topic# callback# options#))
(~'init-source [topic# & options#] (init-source-on
context# sources# topic# options#))
(~'init-receiver [topic# & options#] (init-receiver-on
context# receivers# topic# options#))]
(try
(do ~...@body)
(finally
... cleanup))
which seems like a bit of an abuse, creating an anaphara for each of
the functions. the problem i had with this was the anaphara werent
available when i was outside of my macro (eg in any other function
called from the macro):
(defn start-server [] (receiver "topic" (fn [o m] (println "this is
full of fail"
(with-context [] (start-server))
i also tried implementing it using a protocol and reify, which worked
rather well and felt the 'cleanest' solution, the impl of which is
probably fairly obvious so i wont bother typing it in here. however i
didnt like having to pass an object around everywhere to call methods
on.
my question is simply, what is the most idiomatic solution? im
guessing the protocol and reify, but is the first solution also
reasonable?
again, sorry for the long question - i also typed it all from memory
so apologies for any obvious typos / mistakes, i dont have the code
available on the machine i am using. any insight would be appreciated.
thanks,
gareth
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Re: ANN: Clojure Cookbook
Daniel, If you install lein-search (http://clojars.org/lein-search or http://github.com/Licenser/lein-search) you can do searches like that. lein search mail If you put it in ~/.lein/plugins it will work for all your lein projects and you can even use it to add what you find to your project.clj and to go through all your dependencies and prompt whether your want to update. Scott On Mon, Sep 27, 2010 at 10:01 AM, Daniel Pittman wrote: > Tim Daly writes: > > > There is a movement afoot in the common lisp community to implement > > quicklisp which is similar to the perl cpan site or debian. It would be > > useful if there was a quicklisp (or asdf) for Clojure. Thus you could > > "apt-get" a library for clojure. > > FWIW, having just started out playing with Clojure with a view to building > a > Google App Engine web service — and from a Perl and Debian background: > > The single biggest thing that I have missed has been 'lein search' or so, > which would allow me to search an index of the modules it can access and > tell > me what is available for meeting my current need. > > The second biggest is the lack of a CPAN-alike central service on the web > that > would allow me to do the same, plus review the documentation for candidate > libraries. > > So, um, that would be nice. :) > >Daniel > -- > ✣ Daniel Pittman✉ dan...@rimspace.net☎ +61 401 155 > 707 > ♽ made with 100 percent post-consumer electrons > > -- > 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: Fighting with Emacs ;-)
On Mon, Sep 27, 2010 at 4:03 AM, psfblair wrote: > I found the old thread below, but unfortunately the solution isn't > working for me. If I have a foo.clj file in a buffer and evaluate > region on > > (defn foo [] (+ 1 2)) > > I get > > #'user/foo in the minibuffer. What does your ns form look like? SLIME uses a regex to determine the namespace; it could be that your ns form isn't getting caught by it. -Phil -- 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: Clojure Cookbook
Tim Daly writes: > There is a movement afoot in the common lisp community to implement > quicklisp which is similar to the perl cpan site or debian. It would be > useful if there was a quicklisp (or asdf) for Clojure. Thus you could > "apt-get" a library for clojure. FWIW, having just started out playing with Clojure with a view to building a Google App Engine web service — and from a Perl and Debian background: The single biggest thing that I have missed has been 'lein search' or so, which would allow me to search an index of the modules it can access and tell me what is available for meeting my current need. The second biggest is the lack of a CPAN-alike central service on the web that would allow me to do the same, plus review the documentation for candidate libraries. So, um, that would be nice. :) Daniel -- ✣ Daniel Pittman✉ dan...@rimspace.net☎ +61 401 155 707 ♽ made with 100 percent post-consumer electrons -- 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: Interop question concerning optional args
The vararg at the end of the method is just syntactic sugar for an array, so the "add" method actually takes 4 args, the last being a Resource array. The java compiler just replaces "missing" varargs with an empty array. My guess is that the reflection mechanisms in the compiler just look at type/arity. The Method object has a isVarArg() boolean, so that could be used to allow omitting varargs altogether. That would need to be an enhancement to the clojure compiler, so I opened a ticket: https://www.assembla.com/spaces/clojure/tickets/440-java-method-calls-cannot-omit-varargs On Sep 27, 1:16 pm, JonathanBelolo wrote: > While toying with the Sesame2.3 library, I've come across the > following behavior for the first time. > > This is taken from the api doc for > org.openrdf.repository.base.RepositoryConnectionBase: > > add(Resource subject, URI predicate, Value object, Resource... > contexts) > Adds a statement with the specified subject, predicate and > object to this repository, optionally to one or more named contexts. > > But apparently, Clojure seems to think the optional args are > mandatory... > > (.add con alice RDF/TYPE person) > > No matching method found: add for class > org.openrdf.repository.sail.SailRepositoryConnection > [Thrown class java.lang.IllegalArgumentException] > > So I run > > (grep #".add" (.getMethods (.getClass con))) > > # org.openrdf.repository.base.RepositoryConnectionBase.add(org.openrdf.model. > Resource,org.openrdf.model.URI,org.openrdf.model.Value,org.openrdf.model.Re > source[]) > throws org.openrdf.repository.RepositoryException>) > > Finally the following works... > > (.add con alice RDF/TYPE person (make-array Resource 1)) > nil > > Is this behavior normal? Are optional args mandatory when called with > interop? > > Thanks for your help :) > > Jonathan -- 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
Problems Running tests with fixtures
I suppose I've been looking at this code for too long, so I need a 2nd pair
of eyes on it. I'm not getting some 'test.is' code to run. I'm trying to run
the tests as in fig. 1. Suppose the tests are defined in a file called
utests.clj (fig. 2).
(use 'clojure.test)
(require 'utests)
(run-tests 'utests)
*fig. 1 - run attempts *
(ns utests)
(defn test-fixture-1 [test-func]
(setup-code)
(test-func)
(teardown-code)
)
(use-fixtures :each test-fixture-1)
(deftest test-code []
(= 5 5))
)
*fig. 2 - utests.clj*
*Ran 0 tests containing 0 assertions.*
*0 failures, 0 errors.*
*{:type :summary, :test 0, :pass 0, :fail 0, :error 0}*
*fig. 3 - output*
Q. The thing that I'm missing is...
Thanks in advance
Tim
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Re: Possible to avoid reflection in this deftype in 1.3 alpha1?
I don't know if it makes a difference, but I was doing AOT compilation
on a file nbody.clj containing the program in my message.
I replied to my own message with a workaround that it seems to be
related to the variable 'nbody' having the same name as the one in the
'ns' declaration.
Thanks,
Andy
On Sep 27, 2010, at 4:14 PM, Stuart Halloway wrote:
That's weird. I see no reflection warnings when loading this on 1.3
alpha 1.
Stu
The following program compiles and runs perfectly fine in both 1.2
and 1.3 alpha1. It has no reflection warnings in 1.2, but it does
in 1.3 alpha1. I have tried several variations, but I haven't yet
been able to figure out how to write type declarations that avoid
reflection in 1.3 alpha1. Does anyone know whether this is a bug?
Or perhaps code like this ought to be structured completely
differently in order to avoid reflection, and it was just a fluke
that it worked in 1.2?
Thanks,
Andy
(ns nbody
(:gen-class))
(set! *warn-on-reflection* true)
(definterface IBody
(^double x [])
(^double y [])
(^double z [])
(^double dist [other]))
(deftype Body [^{:unsynchronized-mutable true :tag double} x
^{:unsynchronized-mutable true :tag double} y
^{:unsynchronized-mutable true :tag double} z ]
IBody
(x [this] x)
(y [this] y)
(z [this] z)
(dist [this other]
(let [^Body nbody other
dx (- x (.x nbody)) ; first reflection warning here
dy (- y (.y nbody)) ; second here
dz (- z (.z nbody)) ; third here
dsq (+ (* dx dx)
(+ (* dy dy)
(* dz dz)))]
(Math/sqrt dsq
(defn -main [& args]
(let [b (Body. 0 0 0)]
(println "pos:" (.x b) (.y b) (.z b
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Re: Possible to avoid reflection in this deftype in 1.3 alpha1?
OK, so I happened to stumble across a fix to my program, but I still
wonder whether this is intentional behavior in 1.3 alpha1 or not.
If I change the name 'nbody' in these lines:
(let [^Body nbody other
dx (- x (.x nbody)) ; first reflection warning here
dy (- y (.y nbody)) ; second here
dz (- z (.z nbody)) ; third here
to some name that is not the name of the namespace, like 'nbo', then
the reflection warnings go away:
(let [^Body nbo other
dx (- x (.x nbo)) ; first reflection warning here
dy (- y (.y nbo)) ; second here
dz (- z (.z nbo)) ; third here
If I then change the ns declaration at the top to "ns nbo", the
reflection warnings come back again.
Easy to avoid the problem, once you know.
Andy
On Sep 27, 2010, at 1:58 PM, Andy Fingerhut wrote:
The following program compiles and runs perfectly fine in both 1.2
and 1.3 alpha1. It has no reflection warnings in 1.2, but it does
in 1.3 alpha1. I have tried several variations, but I haven't yet
been able to figure out how to write type declarations that avoid
reflection in 1.3 alpha1. Does anyone know whether this is a bug?
Or perhaps code like this ought to be structured completely
differently in order to avoid reflection, and it was just a fluke
that it worked in 1.2?
Thanks,
Andy
(ns nbody
(:gen-class))
(set! *warn-on-reflection* true)
(definterface IBody
(^double x [])
(^double y [])
(^double z [])
(^double dist [other]))
(deftype Body [^{:unsynchronized-mutable true :tag double} x
^{:unsynchronized-mutable true :tag double} y
^{:unsynchronized-mutable true :tag double} z ]
IBody
(x [this] x)
(y [this] y)
(z [this] z)
(dist [this other]
(let [^Body nbody other
dx (- x (.x nbody)) ; first reflection warning here
dy (- y (.y nbody)) ; second here
dz (- z (.z nbody)) ; third here
dsq (+ (* dx dx)
(+ (* dy dy)
(* dz dz)))]
(Math/sqrt dsq
(defn -main [& args]
(let [b (Body. 0 0 0)]
(println "pos:" (.x b) (.y b) (.z b
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Interop question concerning optional args
While toying with the Sesame2.3 library, I've come across the following behavior for the first time. This is taken from the api doc for org.openrdf.repository.base.RepositoryConnectionBase: add(Resource subject, URI predicate, Value object, Resource... contexts) Adds a statement with the specified subject, predicate and object to this repository, optionally to one or more named contexts. But apparently, Clojure seems to think the optional args are mandatory... (.add con alice RDF/TYPE person) No matching method found: add for class org.openrdf.repository.sail.SailRepositoryConnection [Thrown class java.lang.IllegalArgumentException] So I run (grep #".add" (.getMethods (.getClass con))) #) Finally the following works... (.add con alice RDF/TYPE person (make-array Resource 1)) nil Is this behavior normal? Are optional args mandatory when called with interop? Thanks for your help :) Jonathan -- 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: Possible to avoid reflection in this deftype in 1.3 alpha1?
That's weird. I see no reflection warnings when loading this on 1.3 alpha 1.
Stu
> The following program compiles and runs perfectly fine in both 1.2 and 1.3
> alpha1. It has no reflection warnings in 1.2, but it does in 1.3 alpha1. I
> have tried several variations, but I haven't yet been able to figure out how
> to write type declarations that avoid reflection in 1.3 alpha1. Does anyone
> know whether this is a bug?
>
> Or perhaps code like this ought to be structured completely differently in
> order to avoid reflection, and it was just a fluke that it worked in 1.2?
>
> Thanks,
> Andy
>
> (ns nbody
> (:gen-class))
>
> (set! *warn-on-reflection* true)
>
> (definterface IBody
> (^double x [])
> (^double y [])
> (^double z [])
> (^double dist [other]))
>
> (deftype Body [^{:unsynchronized-mutable true :tag double} x
> ^{:unsynchronized-mutable true :tag double} y
> ^{:unsynchronized-mutable true :tag double} z ]
> IBody
> (x [this] x)
> (y [this] y)
> (z [this] z)
> (dist [this other]
>(let [^Body nbody other
> dx (- x (.x nbody)) ; first reflection warning here
> dy (- y (.y nbody)) ; second here
> dz (- z (.z nbody)) ; third here
> dsq (+ (* dx dx)
> (+ (* dy dy)
>(* dz dz)))]
> (Math/sqrt dsq
>
> (defn -main [& args]
> (let [b (Body. 0 0 0)]
>(println "pos:" (.x b) (.y b) (.z b
>
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Re: exception thrown when passing in nil parameter
Here's one popular form: (defn foo ([a b c] (foo a b c nil)) ([a b c d] (if d ...))) Most multi-arity functions have the same behavior for every arity, with some default argument values. -S On Sep 27, 2:13 pm, Glen Rubin wrote: > I have a function that will accept 3 or 4 parameters. Another > function I have calls it and passes in 4 arguments. Sometimes, the > 4th argument is nil and this causes an error, instead of just calling > the main function as if I passed in 3 arguments. Meaning the main > function sees a 4th parameter with nil value. How do I get it to act > as only 3 parameters were passed in this circumstance? thx -- 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: Fighting with Emacs ;-)
C-c C-k in the .clj buffer is easier and equivalent (or at least very similar) On Sep 27, 12:27 pm, Linus Ericsson wrote: > I recognize that one. The repl haven't loaded the file your editing. > > My (temporary) solution is to do a (load-file "") > after each edit that I want to debug, but that's a bit boring. I guess there > is some kind of reload feature somewhere... > > /Linus > > 2010/9/27 psfblair > > > I found the old thread below, but unfortunately the solution isn't > > working for me. If I have a foo.clj file in a buffer and evaluate > > region on > > > (defn foo [] (+ 1 2)) > > > I get > > > #'user/foo in the minibuffer. If I then evaluate region on > > > (foo) > > > I get 3 in the minibuffer. The slime REPL is giving me a prompt user> > > so I'm assuming it's in the user namespace, but I can't seem to get > > expressions from the text buffer to evaluate in there. > > > On Mar 28, 5:01 am, Michał Marczyk wrote: > > > > On 27 March 2010 22:25, alux wrote: > > > > > But now I see people use the result of this evaluation in their REPL > > > > (I see this in videos, so I cant ask 'em :). This doesnt work at all > > > > for me. I get the result in the minibuffer (this thing at the very > > > > bottom) and thats it. > > > > If the form you evaluate is of the def* variety, it's going to affect > > > the namespace it resides in and not the namespace of the REPL. Thus, > > > if you have e.g. (ns foo) at the top of the file, yet you're working > > > in the user namespace at the REPL, then after using C-x C-e to > > > evaluate a function definition in your file, you'll have to say > > > something like foo/bar to reach it from the REPL. (Or (use :reload-all > > > 'foo), if you prefer.) > > > > If there is no namespace declaration in the file, then the expression > > > will be evaluated in the user namespace, which means that you'll be > > > able to use it straight away if that's your REPL's namespace. (If you > > > say (in-ns 'foo) or (ns foo) at the REPL, then you'll have to say > > > something like user/bar to reach your function.) > > > > 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
Possible to avoid reflection in this deftype in 1.3 alpha1?
The following program compiles and runs perfectly fine in both 1.2 and
1.3 alpha1. It has no reflection warnings in 1.2, but it does in 1.3
alpha1. I have tried several variations, but I haven't yet been able
to figure out how to write type declarations that avoid reflection in
1.3 alpha1. Does anyone know whether this is a bug?
Or perhaps code like this ought to be structured completely
differently in order to avoid reflection, and it was just a fluke that
it worked in 1.2?
Thanks,
Andy
(ns nbody
(:gen-class))
(set! *warn-on-reflection* true)
(definterface IBody
(^double x [])
(^double y [])
(^double z [])
(^double dist [other]))
(deftype Body [^{:unsynchronized-mutable true :tag double} x
^{:unsynchronized-mutable true :tag double} y
^{:unsynchronized-mutable true :tag double} z ]
IBody
(x [this] x)
(y [this] y)
(z [this] z)
(dist [this other]
(let [^Body nbody other
dx (- x (.x nbody)) ; first reflection warning here
dy (- y (.y nbody)) ; second here
dz (- z (.z nbody)) ; third here
dsq (+ (* dx dx)
(+ (* dy dy)
(* dz dz)))]
(Math/sqrt dsq
(defn -main [& args]
(let [b (Body. 0 0 0)]
(println "pos:" (.x b) (.y b) (.z b
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Re: How often do you use REPL?
I use REPL quite a bit. Especially if I'm quickly trying to throw something together. I'd use vimclojure and REPL. In intelliJ, I use REPL for brain storm and testing. On Mon, Sep 27, 2010 at 3:14 PM, Christian Guimaraes wrote: > It's a noob question... I know > > But in my studies I use REPL 80% of the coding time. > > More advanced users still uses REPL so many times? > -- Omnem crede diem tibi diluxisse supremum. -- 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: How often do you use REPL?
A lot. By that, I mean that probably 80% to 100% of the time the REPL is running waiting for your command. And what may change is that you may more and more "send" code to the REPL from your favorite editor. 2 flavors : * keep the full control on what is emitted to the REPL. There are shortcuts for your favorite editor to send the selection, or the top level s expression, to the REPL. * leverage some automation from your IDE : e.g. ccw (plugin for clojure code in Eclipse) has a mode for automatically reloading the namespaces of your project everytime you save a file (in addition to the above mentioned shortcuts) 2010/9/27 Christian Guimaraes > It's a noob question... I know > > But in my studies I use REPL 80% of the coding time. > > More advanced users still uses REPL so many times? > > thanks. > > -- christian guimaraes > > -- > 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: Fighting with Emacs ;-)
I recognize that one. The repl haven't loaded the file your editing. My (temporary) solution is to do a (load-file "") after each edit that I want to debug, but that's a bit boring. I guess there is some kind of reload feature somewhere... /Linus 2010/9/27 psfblair > I found the old thread below, but unfortunately the solution isn't > working for me. If I have a foo.clj file in a buffer and evaluate > region on > > (defn foo [] (+ 1 2)) > > I get > > #'user/foo in the minibuffer. If I then evaluate region on > > (foo) > > I get 3 in the minibuffer. The slime REPL is giving me a prompt user> > so I'm assuming it's in the user namespace, but I can't seem to get > expressions from the text buffer to evaluate in there. > > > On Mar 28, 5:01 am, Michał Marczyk wrote: > > > On 27 March 2010 22:25, alux wrote: > > > > > But now I see people use the result of this evaluation in their REPL > > > (I see this in videos, so I cant ask 'em :). This doesnt work at all > > > for me. I get the result in the minibuffer (this thing at the very > > > bottom) and thats it. > > > > If the form you evaluate is of the def* variety, it's going to affect > > the namespace it resides in and not the namespace of the REPL. Thus, > > if you have e.g. (ns foo) at the top of the file, yet you're working > > in the user namespace at the REPL, then after using C-x C-e to > > evaluate a function definition in your file, you'll have to say > > something like foo/bar to reach it from the REPL. (Or (use :reload-all > > 'foo), if you prefer.) > > > > If there is no namespace declaration in the file, then the expression > > will be evaluated in the user namespace, which means that you'll be > > able to use it straight away if that's your REPL's namespace. (If you > > say (in-ns 'foo) or (ns foo) at the REPL, then you'll have to say > > something like user/bar to reach your function.) > > > > 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: How often do you use REPL?
Why not? The only thing I found very practical (even though it does not yet work 100% (like autoloading the open code in the repl) for me) is the possibility to fire of longer commands and function definitions (or the like) in Slime (or vi-equivalent). The repl is a great way to debug your thoughts, but it's harder to gain the overview to build more complex programs (with more than a few rows or functions, that is). REPL ftw! /Linus 2010/9/27 Christian Guimaraes > It's a noob question... I know > > But in my studies I use REPL 80% of the coding time. > > More advanced users still uses REPL so many times? > > thanks. > > -- christian guimaraes > > -- > 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
How often do you use REPL?
It's a noob question... I know But in my studies I use REPL 80% of the coding time. More advanced users still uses REPL so many times? thanks. -- christian guimaraes -- 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: exception thrown when passing in nil parameter
(defn f ([a b c] ...) ([a b c d] (if d ... (f a b c Not the prettiest solution, I'll grant you; I'm sure someone will come along with something better. But this will work. On Sep 27, 11:13 am, Glen Rubin wrote: > I have a function that will accept 3 or 4 parameters. Another > function I have calls it and passes in 4 arguments. Sometimes, the > 4th argument is nil and this causes an error, instead of just calling > the main function as if I passed in 3 arguments. Meaning the main > function sees a 4th parameter with nil value. How do I get it to act > as only 3 parameters were passed in this circumstance? thx -- 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
exception thrown when passing in nil parameter
I have a function that will accept 3 or 4 parameters. Another function I have calls it and passes in 4 arguments. Sometimes, the 4th argument is nil and this causes an error, instead of just calling the main function as if I passed in 3 arguments. Meaning the main function sees a 4th parameter with nil value. How do I get it to act as only 3 parameters were passed in this circumstance? thx -- 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: return index of a value
interesting! thx guys! On Sep 27, 10:45 am, Glen Rubin wrote: > I have a vector of numbers > > [0 99 3334 53 2 5 99 2 55 63] > > I'd like to find the first index of a particular value. For example > if the value was 99 then I want to return 1, b/c the index of 99 is > 1. I can do this with a loop/recur structure comparing each value in > the list to my desired value, however am wondering if there isn't a > built-in for doing so?? thanks again! -- 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: finding value nearest x
ok, thx. just trying to keep myself to a high standard while learning this stuff ;) On Sep 27, 11:12 am, Michael Gardner wrote: > On Sep 27, 2010, at 9:59 AM, Glen Rubin wrote: > > > yes correct. but i can write a fn to determine the index of the > > minimum distance in my new list? > > > that index applied to my original list will give me the value back. > > and this still would involve fewer calculations i think. > > Do you have a particular reason to be concerned about performance here? Don't > worry about it unless profiling tells you it's a bottleneck for your program. > > And I doubt it will actually give better performance anyway, even with > min-key evaluating f more times than is necessary, because your f is so > inexpensive to calculate. -- 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: Macro expansion problem
Thanks for your reply :) The context: I am developing a wrapper generator that takes a Java class and generates a Clojure wrapper, with a function for each method etc. The purpose is to have nice wrappers, so your code is "cleaner" as with all that Java calls. And it can ba a basis for more convenient wrappers. The generation of normal functions is easy but there is one case that causes me some trouble: If there are methods that are static and non- static with the same name and parameter count. So my first thought was to define a multimethod, depending on the first parameter (which has to be an instance of the class in case of non-static) with variable number of args together with two macros, one for a static method call and one for a simple method call, that take that variable arglist and expand to the right call. But I don't need the macros! Five minutes ago, I didn't know that multimethods can have multiple function-bodies (and therefore multiple different parameter lists). So I can generate the code for all possible parameter lists without a variable "& args" parameter and without the macros. Will be simple :) -- 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: finding value nearest x
On Sep 25, 11:41 am, Glen Rubin wrote: > I have a list of numbers and I want to find the one that is closest to > 136. Is there an operator for performing this kind of operation or do > I need to to do it algorithmically? I think the normal way to do this is a k-d tree: http://en.wikipedia.org/wiki/Kd-tree Adam -- 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: Clojure Cookbook
I believe http://clojars.org is intended to fill the purpose you describe, except using Leiningen or Maven instead of apt-get. I do not know yet how good its inter- library dependency info is, but there is some there. Andy On Sep 27, 2010, at 9:12 AM, Tim Daly wrote: There is a movement afoot in the common lisp community to implement quicklisp which is similar to the perl cpan site or debian. It would be useful if there was a quicklisp (or asdf) for Clojure. Thus you could "apt-get" a library for clojure. Tim Daly On 9/27/2010 1:47 AM, David Sletten wrote: Ladies and Gentlemen, I present for your viewing pleasure the Clojure Cookbook (beta :) ): http://www.gettingclojure.com/cookbook:clojure-cookbook Gregg Williams has set up a framework at Getting Clojure to gather material, primarily focused on newbies, on how to flatten the learning curve. The cookbook is a part of that vision. Inspired of course by O'Reilly's Perl Cookbook, the cookbook aims to present concrete examples along with brief discussions of specific tasks a new Clojure programmer might want to accomplish. The cookbook should complement the existing Clojure books and other documentation and provide additional examples that the other resources don't have time or space to consider. At this point I have seeded the cookbook with approximately 20 recipes. I want to emphasize that I hope this will be a community resource with others providing content or even fixing my explanations where they are incorrect or off target. At the moment the cookbook is essentially read-only aside from the comments section at the bottom of each page. But once we get a sense of the community response the site will be opened for anyone to contribute. Please take a look at the site and let us know what works and what needs to be fixed. And start thinking up your own recipes. Thanks. Have all good days, David Sletten -- 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: Clojure Cookbook
very good! On Mon, Sep 27, 2010 at 1:12 PM, Tim Daly wrote: > There is a movement afoot in the common lisp community to > implement quicklisp which is similar to the perl cpan site > or debian. It would be useful if there was a quicklisp (or > asdf) for Clojure. Thus you could "apt-get" a library for > clojure. > > Tim Daly > > > On 9/27/2010 1:47 AM, David Sletten wrote: > >> Ladies and Gentlemen, >> >> I present for your viewing pleasure the Clojure Cookbook (beta :) ): >> http://www.gettingclojure.com/cookbook:clojure-cookbook >> >> Gregg Williams has set up a framework at Getting Clojure to gather >> material, primarily focused on newbies, on how to flatten the learning >> curve. >> >> The cookbook is a part of that vision. Inspired of course by O'Reilly's >> Perl Cookbook, the cookbook aims to present concrete examples along with >> brief discussions of specific tasks a new Clojure programmer might want to >> accomplish. The cookbook should complement the existing Clojure books and >> other documentation and provide additional examples that the other resources >> don't have time or space to consider. >> >> At this point I have seeded the cookbook with approximately 20 recipes. I >> want to emphasize that I hope this will be a community resource with others >> providing content or even fixing my explanations where they are incorrect or >> off target. At the moment the cookbook is essentially read-only aside from >> the comments section at the bottom of each page. But once we get a sense of >> the community response the site will be opened for anyone to contribute. >> >> Please take a look at the site and let us know what works and what needs >> to be fixed. And start thinking up your own recipes. >> >> Thanks. >> >> Have all good days, >> David Sletten >> >> >> >> >> > -- > 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 > -- Diullei Gomes Desenvolvedor .NET http://diullei.com/ http://twitter.com/diullei -- 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: finding value nearest x
On Sep 27, 2010, at 9:59 AM, Glen Rubin wrote: > yes correct. but i can write a fn to determine the index of the > minimum distance in my new list? > > that index applied to my original list will give me the value back. > and this still would involve fewer calculations i think. Do you have a particular reason to be concerned about performance here? Don't worry about it unless profiling tells you it's a bottleneck for your program. And I doubt it will actually give better performance anyway, even with min-key evaluating f more times than is necessary, because your f is so inexpensive to calculate. -- 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: return index of a value
On Sep 27, 2010, at 9:45 AM, Glen Rubin wrote: > I have a vector of numbers > > [0 99 3334 53 2 5 99 2 55 63] > > I'd like to find the first index of a particular value. For example > if the value was 99 then I want to return 1, b/c the index of 99 is > 1. I can do this with a loop/recur structure comparing each value in > the list to my desired value, however am wondering if there isn't a > built-in for doing so?? thanks again! In general, 'some' is used for linear searches. Given a vector 'v': (some #(and (= 99 (v %)) %) (range 0 (count v))) This is awkward because you're asking for the index and not the value itself. Index-based array manipulation is not often used in Clojure. -- 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: return index of a value
Hi Glen,
Finding the *first* index isn't very Clojurish, what you want is to find *all*
the indexes, lazily. Then if you want the first one, just call first.
(use '[clojure.contrib.seq-utils :only (positions)])
(positions #{99} [0 99 3334 53 2 5 99 2 55 63])
-> (1 6)
Cheers,
Stu
> I have a vector of numbers
>
> [0 99 3334 53 2 5 99 2 55 63]
>
> I'd like to find the first index of a particular value. For example
> if the value was 99 then I want to return 1, b/c the index of 99 is
> 1. I can do this with a loop/recur structure comparing each value in
> the list to my desired value, however am wondering if there isn't a
> built-in for doing so?? thanks again!
>
> --
> 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
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> http://groups.google.com/group/clojure?hl=en
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Re: finding value nearest x
yes correct. but i can write a fn to determine the index of the minimum distance in my new list? that index applied to my original list will give me the value back. and this still would involve fewer calculations i think. On Sep 27, 10:50 am, Michael Gardner wrote: > On Sep 27, 2010, at 9:28 AM, Glen Rubin wrote: > > > It occurs to me that another way of doing this is to map a new list > > and then use the min fn. something like: > > > (apply min (map #(Math/abs (- % 136)) xs)) > > > maybe this is better and involves less calculations? > > That gives you the minimum distance from 136, not the value itself. You can't > get back the original value afterwards either, because you don't know whether > to subtract or add the distance from 136. -- 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: finding value nearest x
On Sep 27, 2010, at 9:28 AM, Glen Rubin wrote: > It occurs to me that another way of doing this is to map a new list > and then use the min fn. something like: > > (apply min (map #(Math/abs (- % 136)) xs)) > > maybe this is better and involves less calculations? That gives you the minimum distance from 136, not the value itself. You can't get back the original value afterwards either, because you don't know whether to subtract or add the distance from 136. -- 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
return index of a value
I have a vector of numbers [0 99 3334 53 2 5 99 2 55 63] I'd like to find the first index of a particular value. For example if the value was 99 then I want to return 1, b/c the index of 99 is 1. I can do this with a loop/recur structure comparing each value in the list to my desired value, however am wondering if there isn't a built-in for doing so?? thanks again! -- 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: finding value nearest x
It occurs to me that another way of doing this is to map a new list and then use the min fn. something like: (apply min (map #(Math/abs (- % 136)) xs)) maybe this is better and involves less calculations? On Sep 25, 2:19 pm, Glen Rubin wrote: > min-key looks good! thx guys!!! > > On Sep 25, 10:44 am, Nicolas Oury wrote: > > > > > On Sat, Sep 25, 2010 at 3:40 PM, Jules wrote: > > > Maybe this: (min-key #(abs (- % 136)) xs) > > > Wouldn't that be (apply min-key #(abs (- % 136)) xs)? -- 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: Clojure Cookbook
There is a movement afoot in the common lisp community to implement quicklisp which is similar to the perl cpan site or debian. It would be useful if there was a quicklisp (or asdf) for Clojure. Thus you could "apt-get" a library for clojure. Tim Daly On 9/27/2010 1:47 AM, David Sletten wrote: Ladies and Gentlemen, I present for your viewing pleasure the Clojure Cookbook (beta :) ): http://www.gettingclojure.com/cookbook:clojure-cookbook Gregg Williams has set up a framework at Getting Clojure to gather material, primarily focused on newbies, on how to flatten the learning curve. The cookbook is a part of that vision. Inspired of course by O'Reilly's Perl Cookbook, the cookbook aims to present concrete examples along with brief discussions of specific tasks a new Clojure programmer might want to accomplish. The cookbook should complement the existing Clojure books and other documentation and provide additional examples that the other resources don't have time or space to consider. At this point I have seeded the cookbook with approximately 20 recipes. I want to emphasize that I hope this will be a community resource with others providing content or even fixing my explanations where they are incorrect or off target. At the moment the cookbook is essentially read-only aside from the comments section at the bottom of each page. But once we get a sense of the community response the site will be opened for anyone to contribute. Please take a look at the site and let us know what works and what needs to be fixed. And start thinking up your own recipes. Thanks. Have all good days, David Sletten -- 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: Lazytest 1.0.0 (beta)
Don't have any specific suggestion at the moment. I'm planning on adding a REPL runner that will do something similar to the code you posted. -S On Sep 27, 5:52 am, faenvie wrote: > i am trying to use lazytest with eclipse + ccw ? > > lazytest.watch does not work for me so far. > so i run my lazytests via: > > (ns myapp.runtests > (:require lazytest.runner.console > lazytest.color > lazytest.report.nested)) > > ; switch ansi-coloring off > (lazytest.color/set-colorize false) > > ; execute tests for specified namespaces > (doseq [sym ['myapp.tests1 'myapp.tests2]] > (println "Loading" sym) > (require sym) > (println "Running tests in" sym) > (lazytest.report.nested/report > (lazytest.runner.console/run-tests sym))) > > any better solutions ? > > On Sep 24, 9:38 pm, Stuart Sierra wrote: > > > > >http://github.com/stuartsierra/lazytest > > > My attempt to steal all the good ideas from clojure.test, Circumspec, > > ClojureCheck, RSpec, Spock, ScalaTest, etc. Kudos to all those > > authors for all their great work. > > > -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: ANN: Clojure Cookbook
Nice! -- 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 programs require much more memory in Clojure 1.3 alpha1
> Anyone know any command line options for HotSpot that make it work harder to > compact things down into the smallest space possible, no matter what? I am > aware of several pages of documentation on HotSpot's GC options, and I've > been reading some of them, but it is a lot to wade through. There is an -XX:+UseCompressedOops which may be relevant. In any case, is the actual live heap size larger (as in, the heap size after a full GC, presuming you're running with the default throughput collector), or are you comparing the growth of the heap size? In particular, heap size is a function of, among others, the amount of time spent GC:ing. The discrepancy may potentially be due to Hotspot increasing the heap size for efficiency policy reasons rather than necessarily that the live set is in fact bigger with Hotspot. You might start by running with -XX:+PrintGC -XX:+PrintGCDetails and look at the heap size after a full collection. -- / 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: Hiccup with Sequence
Nicolas, Yes, that's solved the problem. Many thanks for you swift help. Paul. On Sep 27, 12:12 pm, Nicolas Oury wrote: > doseq do not return anything. (It is for side-effect only). > > You might be looking for 'for'. > > (doc for) > - > clojure.core/for > ([seq-exprs body-expr]) > Macro > List comprehension. Takes a vector of one or more > binding-form/collection-expr pairs, each followed by zero or more > modifiers, and yields a lazy sequence of evaluations of expr. > Collections are iterated in a nested fashion, rightmost fastest, > and nested coll-exprs can refer to bindings created in prior > binding-forms. Supported modifiers are: :let [binding-form expr ...], > :while test, :when test. > > (take 100 (for [x (range 1) y (range 100) :while (< y x)] [x > y])) > > > > > > On Mon, Sep 27, 2010 at 11:25 AM, Paul wrote: > > Hi all, > > > I'm trying to output the items from a sequence into a HTML list using > > the Hiccup HTML builder, but am having problems. > > > Here is the code I think 'should' work, but nothing after the ':ul' is > > passed back to the response: > > > (html > > [:html > > [:body > > [:ul > > (doseq [item myseq] [:li item]) > > ] > > ] > > ] > > ) > > > Can anyone see why this is not working? > > > Thanks, > > > Paul. > > > -- > > 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 > > -- > Sent from an IBM Model M, 15 August 1989. -- 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: Lazytest 1.0.0 (beta)
Hi, 2010/9/27 faenvie > i am trying to use lazytest with eclipse + ccw ? > You note that you're using ccw, is that because you have a clue that there could be something related to the "lazytest-ccw" combo in the issue you're facing ? > > lazytest.watch does not work for me so far. > so i run my lazytests via: > > (ns myapp.runtests > (:require lazytest.runner.console > lazytest.color >lazytest.report.nested)) > > ; switch ansi-coloring off > (lazytest.color/set-colorize false) > > ; execute tests for specified namespaces > (doseq [sym ['myapp.tests1 'myapp.tests2]] > (println "Loading" sym) > (require sym) > (println "Running tests in" sym) > (lazytest.report.nested/report > (lazytest.runner.console/run-tests sym))) > > any better solutions ? > > > On Sep 24, 9:38 pm, Stuart Sierra wrote: > > http://github.com/stuartsierra/lazytest > > > > My attempt to steal all the good ideas from clojure.test, Circumspec, > > ClojureCheck, RSpec, Spock, ScalaTest, etc. Kudos to all those > > authors for all their great work. > > > > -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 > -- 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: Macro expansion problem
Difficult problem. macro are syntactic tools. So they are not made to evaluate things at runtime. You could expand to something that call eval at runtime but it is not a good idea (It involves the compiler at each call) If your (rest alist) is known at macro-expansion time, then it can work but to help, I would need to know the context in which you are using it. What you want to do would be done by apply for functions. However, as far as I know, apply do not work on method calls. If you look at the problem from the java point of view, it is quite hard to write some code that call a method with an unkown number of argument without using reflection. If you have a fix number of argument, you can do this: (defmacro call-5 "Calls an instance method on a given object with a list of params." [obj method-name params] `(apply (fn [x1# x2# x3# x4# x5#] (. ~obj ~(symbol method-name) x1# x2# x3# x4# x5#) ) ~params)) You can also write a macro that takes the arity as a parameter and do that trick. You can also generate an anonymous function with multiple arity `(apply (fn ([x1#] (. ~obj ~(symbol method-name) x1# )) ([x1# x2#] (. ~obj ~(symbol method-name) x1# x2#)) ([x1# x2# x3#] (. ~obj ~(symbol method-name) x1# x2# x3#)) ... up to enough (20 should do the trick) ~params) However, ti might be easier to explain what you are trying to achieve in a bigger context to see if there is a simpler path. Best, Nicolas. On Mon, Sep 27, 2010 at 6:52 AM, stefanmuenchow wrote: > I am a macro newbie... I want to create a macro that calls a function > with a given name and a parameter list on a given object. My first > idea was like this: > > (defmacro call > "Calls an instance method on a given object with a list of params." > [obj method-name params] > `(. ~obj ~(symbol method-name) ~...@params)) > > It works fine, if the param list is a simple list, like "(1 2 3 4)", > but if params is created from an existing list, like "(rest alist)" > then it doesn't work. So params has to be evaluated first and then the > single params has to be expanded. How do I do that? I tried it with a > let block then I got other errors. > > -- > 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 -- Sent from an IBM Model M, 15 August 1989. -- 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: Hiccup with Sequence
doseq do not return anything. (It is for side-effect only). You might be looking for 'for'. (doc for) - clojure.core/for ([seq-exprs body-expr]) Macro List comprehension. Takes a vector of one or more binding-form/collection-expr pairs, each followed by zero or more modifiers, and yields a lazy sequence of evaluations of expr. Collections are iterated in a nested fashion, rightmost fastest, and nested coll-exprs can refer to bindings created in prior binding-forms. Supported modifiers are: :let [binding-form expr ...], :while test, :when test. (take 100 (for [x (range 1) y (range 100) :while (< y x)] [x y])) On Mon, Sep 27, 2010 at 11:25 AM, Paul wrote: > Hi all, > > I'm trying to output the items from a sequence into a HTML list using > the Hiccup HTML builder, but am having problems. > > Here is the code I think 'should' work, but nothing after the ':ul' is > passed back to the response: > > (html > [:html > [:body > [:ul > (doseq [item myseq] [:li item]) > ] > ] > ] > ) > > Can anyone see why this is not working? > > Thanks, > > Paul. > > -- > 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 -- Sent from an IBM Model M, 15 August 1989. -- 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: Fighting with Emacs ;-)
I found the old thread below, but unfortunately the solution isn't working for me. If I have a foo.clj file in a buffer and evaluate region on (defn foo [] (+ 1 2)) I get #'user/foo in the minibuffer. If I then evaluate region on (foo) I get 3 in the minibuffer. The slime REPL is giving me a prompt user> so I'm assuming it's in the user namespace, but I can't seem to get expressions from the text buffer to evaluate in there. On Mar 28, 5:01 am, Michał Marczyk wrote: > On 27 March 2010 22:25, alux wrote: > > > But now I see people use the result of this evaluation in their REPL > > (I see this in videos, so I cant ask 'em :). This doesnt work at all > > for me. I get the result in the minibuffer (this thing at the very > > bottom) and thats it. > > If the form you evaluate is of the def* variety, it's going to affect > the namespace it resides in and not the namespace of the REPL. Thus, > if you have e.g. (ns foo) at the top of the file, yet you're working > in the user namespace at the REPL, then after using C-x C-e to > evaluate a function definition in your file, you'll have to say > something like foo/bar to reach it from the REPL. (Or (use :reload-all > 'foo), if you prefer.) > > If there is no namespace declaration in the file, then the expression > will be evaluated in the user namespace, which means that you'll be > able to use it straight away if that's your REPL's namespace. (If you > say (in-ns 'foo) or (ns foo) at the REPL, then you'll have to say > something like user/bar to reach your function.) > > 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
Hiccup with Sequence
Hi all, I'm trying to output the items from a sequence into a HTML list using the Hiccup HTML builder, but am having problems. Here is the code I think 'should' work, but nothing after the ':ul' is passed back to the response: (html [:html [:body [:ul (doseq [item myseq] [:li item]) ] ] ] ) Can anyone see why this is not working? Thanks, Paul. -- 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: Lazytest 1.0.0 (beta)
i am trying to use lazytest with eclipse + ccw ? lazytest.watch does not work for me so far. so i run my lazytests via: (ns myapp.runtests (:require lazytest.runner.console lazytest.color lazytest.report.nested)) ; switch ansi-coloring off (lazytest.color/set-colorize false) ; execute tests for specified namespaces (doseq [sym ['myapp.tests1 'myapp.tests2]] (println "Loading" sym) (require sym) (println "Running tests in" sym) (lazytest.report.nested/report (lazytest.runner.console/run-tests sym))) any better solutions ? On Sep 24, 9:38 pm, Stuart Sierra wrote: > http://github.com/stuartsierra/lazytest > > My attempt to steal all the good ideas from clojure.test, Circumspec, > ClojureCheck, RSpec, Spock, ScalaTest, etc. Kudos to all those > authors for all their great work. > > -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
Macro expansion problem
I am a macro newbie... I want to create a macro that calls a function with a given name and a parameter list on a given object. My first idea was like this: (defmacro call "Calls an instance method on a given object with a list of params." [obj method-name params] `(. ~obj ~(symbol method-name) ~...@params)) It works fine, if the param list is a simple list, like "(1 2 3 4)", but if params is created from an existing list, like "(rest alist)" then it doesn't work. So params has to be evaluated first and then the single params has to be expanded. How do I do that? I tried it with a let block then I got other errors. -- 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 programs require much more memory in Clojure 1.3 alpha1
Hmmm. I did some additional experiments using the JRockit JVM on Windows XP, and JRockit not only has equivalent memory usage for Clojure 1.2 and 1.3 alpha1, but it can also run these programs with significantly less memory than HotSpot. HotSpot is similar, but not identical, in its memory requirements on all of Mac, Linux, and Windows XP. This particular program has lots of small things allocated (e.g. one java.lang.String per line, and also a LazySeq and Cons created by lazy- seq in line-seq), and while it is traversing that str is internally using StringBuilder to create one big large string of the whole input file's contents. I am guessing that HotSpot's default GC parameters are not good for this memory usage pattern, and somehow JRockit gets it right by default. Anyone know any command line options for HotSpot that make it work harder to compact things down into the smallest space possible, no matter what? I am aware of several pages of documentation on HotSpot's GC options, and I've been reading some of them, but it is a lot to wade through. Thanks, Andy On Sep 26, 2010, at 4:30 PM, Andy Fingerhut wrote: While updating the benchmark programs I wrote for the shootout web site for 1.3 alpha1, I came across a program that required much more memory to complete in 1.3 than it did in 1.2. I boiled it down to a simpler program that has similar properties. (ns filestr2 (:gen-class)) (defn -main [& args] (with-open [br (java.io.BufferedReader. *in*)] (let [dna-str (apply str (line-seq br))] (println "len=" (count dna-str (. System (exit 0))) I've checked that the function apply, str, and line-seq are identical between those two Clojure versions, except for a few minor things like type declarations and static declarations added in 1.3.0- alpha1. I'm curious if anyone can explain the cause of this significant extra memory. As an example of what I mean, when run on an input file with about 125 million characters, it requires 932 Mbytes with Clojure 1.2, but 1,736 Mbytes with Clojure 1.3 alpha1 (using the - Xmx command line option to the JVM). That was on my Mac, and I've seen similar but not identical results on an Ubuntu system. You can read more details if you are curious in the README file of this tarball: http://homepage.mac.com/jafingerhut/files/private/toomuch1.tar.bz2 It also includes a program that uses binary search to find the smallest memory required in order for the program to succeed, to the nearest 8 MB. Thanks, Andy -- 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 code dramatically slower in Clojure 1.3 Alpha 1?
Thanks for the info. I'd need to research how clojure.lang.BigInt differs from java.math.BigInteger, but I'm sure that adding the extra case for BigInt in the multimethods wouldn't be too hard. I'm still stumped as to why expt and sqrt would be 100x slower. My first thought is that the loop/recur machinery has changed in 1.3, to support primitives in the recur, so perhaps there's some extra back and forth boxing/unboxing going on, or perhaps loop/recur is just fundamentally slower now? Another possibility is that all the literal numbers are now longs instead of Integers, so maybe that's slowing down the computations? I'd be curious to know whether explicitly boxing everything in the second line of expt-int helps the performance at all (along with the ' math operators), i.e., (defn- expt-int [base pow] (loop [n pow, y (num 1), z base] to (defn- expt-int [base pow] (loop [n (num pow), y (num 1), z (num base)] -- 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
