Questions / guidelines for adopting Clojure

Hi all! I've been playing around with Clojure in the last couple of days. Very interesting! However, I have never used a non-OO, lispy, pure functional language before and several questions popped up while digging deeper into the Clojure world. I hope you don't mind if I post them together in one

Re: Questions / guidelines for adopting Clojure

Thanks a lot to everbody for the great responses! They certainly helped a lot! Cheers, Roman --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegrou

-> with anonymous functions

Hi there! Lets assume I have this map: user=> (def person {:name "Father" :childs [{:name "Son" :age 10}]}) Testing: user=> (-> person :childs first) {:name "Son", :age 10} Now lets filter the child map: user=> (def only-name (fn [m] (select-keys m [:name]))) user=> (-> person :childs first

Re: -> with anonymous functions

Thanks for the explanation! So the solution is much simpler: user=> (-> person :childs first (select-keys [:name])) {:name "Son"} Cool :-) On Sep 22, 3:26 pm, Jarkko Oranen wrote: > On Sep 22, 3:58 pm, Roman Roelofsen > wrote: > > > > > Hi the

Re: Adding Classpaths On The Fly

Hi, I am currently working on a Clojure / OSGi integration: www.ogeesource.org The goal is to extend Clojure with a module-like runtime, not to fully convert Clojure and Clojure-based applications to OSGi (which would be quite hard anyway). So far you can add new modules at runtime and therefor

Re: Does OSGi make sense for Clojure?

@Mark: I doubt that this will work. Unloading a namespace would mean to remove a class from a classloader and this does not work in Java. OSGi handles this by removing the bundle's classloader completely. @All: The huge added value that OSGi still has is multi-version support. Lets say I want to

Re: Statics in clojure.lang.RT

> Plus, if you use a shared loader for most interfaces, clojure instances will > be able to share persistent data and closures. Nope, I tried this and it didn't work. The classloader explicitly complained that e.g. Var and RT have not been loaded by the same classloader :-/ --~--~-~--~--

Re: Statics in clojure.lang.RT

2009/10/12 Christophe Grand : > On Mon, Oct 12, 2009 at 12:00 PM, Roman Roelofsen > wrote: >> >> > Plus, if you use a shared loader for most interfaces, clojure instances >> > will >> > be able to share persistent data and closures. >> >> Nop

Re: Embedding Clojure in NetKernel

Do you mind sharing the links? I am interested in it as well. Thanks! Roman 2009/10/28 Tony Butterfield : > > Tom Hicks has just pointed me to an old thread which answers > questions about namespaces and isolation. Let me read and > absorb all that work first - I suspect it answers a lot of my

Re: Continuous Integration Server & Maven/Ivy Repo

It seems that only directory listings are disabled since http://build.clojure.org/org/clojure/clojure-lang/maven-metadata.xml is accessible. Roman 2009/11/4 Stuart Sierra : > > I don't think that URL works as a Maven/Ivy repository, because > http://build.clojure.org/org/clojure doesn't exist.

Re: Continuous Integration Server & Maven/Ivy Repo

d of "clojure- > lang", i.e. http://build.clojure.org/org/clojure/clojure/maven-metadata.xml > > That URL doesn't work. > -SS > > > On Nov 4, 10:50 am, Roman Roelofsen > wrote: >> It seems that only directory listings are disabled since >> >>

Re: 'sync' call in writeClassFile

I am a Linux user as well and this indeed sounds a bit alarming (but I haven't tested it on my machine yet, though...) Does somebody has a bit more information about the reason, current state, etc.? Thanks! 2009/11/28 David Brown : > This commit: > >     commit 5577a47a390782d7ab911c2e3c4c8be1b03

Re: Generalizing -> & ->>

Are there any plans to add -$> to core or contrib? 2009/11/13 Laurent PETIT : > Oh yes, thanks for refreshing my memory. > And indeed it makes sense to place the question mark in the "questioned" side > :) > > 2009/11/13 Wilson MacGyver : >> Yes, it's groovy, and it's "?." It's called safe naviga

Disabling ContextClassLoader

It seems that Clojure heavily uses the ContextClassLoader to load classes and compile clj files. Is there a way to disable this behaviour and tell the Clojure runtime to always use the ClassLoader where the .clj or .class file originally came from? I found some flags in the RT class but I am not s

Re: Semantic Versioning

Dealing with version numbers at build time is quite easy with tool like Maven. The important thing is that everyone agrees on the same version semantics (great summary [1]). Putting some more tooling around this should be a good idea, yes. However, the problem in Java is dealing with versions at r

Re: Semantic Versioning

> Talking of semantics, do you think the one I enumerated would work? > I'll certainly try to implement this concept, but I have many other > projects on the table right now, so it might take a while before I > start working on it. Yes, it looks good. The key thing is that all users/developers agr

Re: Full Disclojure - I Need Topics!

2010/1/25 Mark Engelberg : > Debugging techniques, including: > * How to make sense of Clojure's stack traces. > * How to use Java debugging and profiling tools with Clojure. +1 -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, s

ClojureQL insert data from map

Hi, when querying data in clojureql, the result is a list of maps. I often directly return this list (or a map) from my "db-logic" functions because my domain logic operates on these maps. However, I am not able to go the other way around, e.g. take the map and tell clojureql to insert/update a ta

Removing (gensym) in macro

Hi, just for practicing Clojure's macros I wrote the following create-java-list macro. (defmacro create-java-list [& forms] (let [prefixfn (fn [obj form] (cons (symbol ".") (cons obj form))) lname (gensym)] `(let [~lname (java.util.ArrayList.)] ~@(map (partial prefixfn lnam

Re: Removing (gensym) in macro

> I don't see a compelling reason for such a macro. At least not in this > simple case. I agree. As I said, the purpose of this macro was purely for learning and understanding macros ;-) -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this

Re: Removing (gensym) in macro

> It doesn't work because the scope of lname# is limited to the `(). > However lname is used in a ~@() which leaves the `() and enters the > enclosing environment (in this case the macros). There the lname# is > not valid. Ah, that makes sense, thanks! Is using (gensym) the common solution here? S

REST library

Hi, does someone knows a good Clojure REST framework? It should help with URL destructuring and maybe creating JSON return data etc. Cheers, Roman -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegr

Re: REST library

Shantanu Kumar wrote: > On Feb 17, 3:05 pm, Roman Roelofsen > wrote: > >> Hi, >> >> does someone knows a good Clojure REST framework? It should help with >> URL destructuring and maybe creating JSON return data etc. >> > > You can t

Re: Too many arguments to if

Either this, or use the "when" form. http://clojuredocs.org/clojure_core/clojure.core/when 2011/7/11 Tassilo Horn : > Antonio Recio writes: > > Hi Antonio, > >> I get the error "Too many arguments to if" with this. Do you have any >> suggestion? > > `if' expects exacly one test, one then-form, an