Warning unboxing of primitives
Dear all, I am writing a data structure that does a lot of arithmetic operations (+, - , bit-shifting, bit masking...) I did my best to use primitive types, but I am not sure it works everywhere. Is there a way of being warned of unboxings to primitives, with the RC1 of 1.2? (I think it might be better to warn on unboxing than on boxing, but I am not sure and I would be happy with any. Here is the rational : most of the time boxing happens for a reason (call to something or storage in a data structure, for example) , but unboxing happens when you wanted primitive and did not managed to keep things primitive) 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: Why no tail call optimization
On 3 August 2010 04:16, Dan Kersten dkers...@gmail.com wrote: Why can't the clojure bytecode compiler hand-perform this like functional languages do when compiling to native code? Because bytecode attempting to manipulate the stack and jump around (unrestricted goto-like) in other ways than through the usual JVM method call mechanisms would not pass verification (the first step of the bytecode loading process on the JVM). Is it to keep the clojure compiler fast (for dynamic runtime compilation), since performing tail call optimisation presumably requires a bunch of extra checks and more complex code generation? Perhaps this could be done on AOT compilation? TCO adds no complexity at all when the generated object code handles its own stack, subroutine calling conventions etc. A compiler targeting native code has the option of simply not storing a new return address on the stack when compiling a tail call (if the arguments to the current subrouting where passed in registers; if they were passed in a stack frame, it can simply be popped, with the return address saved and reused for the tail call). On the JVM it is impossible, because the generated object code (JVM bytecode) is not permitted to do this sort of thing. Interestingly, [Erjang][1] (a port of Erlang to the JVM) apparently performs TCO while claiming to stay reasonably fast. The gimmick involved is apparently a particularly smart implementation of trampolining. Read more about it [here][2]. I have a hunch that this is a no-go for Clojure (partly because Clojure tends to insist on staying close to the platform -- which has significant benefits -- and partly because I'm not sure if this kind of thing wouldn't disagree with Clojure's extremely dynamic nature... I haven't thought this through that well, though, so maybe this is nonsense). At any rate, it is interesting. Sincerely, Michał [1] git://github.com/krestenkrab/erjang [2] http://wiki.github.com/krestenkrab/erjang/how-erjang-compiles-tail-recursion -- 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 Job Opportunity
Can a person outside US apply? On Aug 3, 6:44 am, Jack_Kennedy - AVID jkennedy1...@gmail.com wrote: Looking for a Senior Software Engineer with experience working with Clojure to join a fantastic company in the Boston area. This person will be responsible for designing and developing next generation software for the purpose of delivering mobile content running on a large network of servers. If interested please call me at 617-951-1891. Relocation is offered for this position. -- 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: Records can't be treated as functions anymore
Karl, It is a common mistake to think that callability, corresponding to the clojure.lang.IFn interface, is part of the persistent map contract (I've done it myself, as did many others a Conj labs :). It is not. It is actually just a feature of clojure.lang.PersistentHashMap (and the other clojure map implementations). I haven't looked at the compiler, but I think that defrecord creates a class that implements clojure.lang.IPersistentMap (among others). Note, Christophe pointed out to me: this is also relevant when you are extending a protocol to clojure.lang.IPersistentMap: don't rely on callability when accessing the map (this was the mistake I made). Makes sense. Thanks, Karl. Regards, BG -- Baishampayan Ghose b.ghose at gmail.com -- 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: Why no tail call optimization
Can one not detect that a recursive call is a tail call and then transform the AST so that its iterative instead - ie, not use the stack besides for initial setup of local variables (which then get reused in each recursive tail-call). Isn't this how its done in native compiled languages with TCO? How is this different from generating bytecode for iterative loops in imperative languages, or from what recur does? Alternatively, why can't the tail call be detected and converted into recur? I'm guessing that the problem is detecting tal calls - but why; speed of dynamic compilation? Something else? Obviously I'm missing something fundamental here - can somebody explain to me what it is? Thanks! On 3 August 2010 05:54, Wilson MacGyver wmacgy...@gmail.com wrote: as Rich Hickey stated question: Is it fundamentally impossible to do TCO on JVM due to current JVM lack of primitives to do so? Would TCO ever be possible on the JVM without a new JVM design? rhickey: TCO is easy if you are an interpreter - see SISC Scheme. Using Java's call stack, the JVM would have to provide it. There are no fundamental technical difficulties, but potential issues for the security model, which uses the call stack to ensure privileges. On Mon, Aug 2, 2010 at 10:16 PM, Dan Kersten dkers...@gmail.com wrote: Why can't the clojure bytecode compiler hand-perform this like functional languages do when compiling to native code? Is it to keep the clojure compiler fast (for dynamic runtime compilation), since performing tail call optimisation presumably requires a bunch of extra checks and more complex code generation? Perhaps this could be done on AOT compilation? On Aug 3, 2:58 am, Frederick Polgardy f...@polgardy.com wrote: It means that the JVM doesn't look at method calls and figure out that they're in tail call position and optimize them. You can hand-write code that performs a goto in a tight loop (like recur does), but means you can't assume that method calls in general will be tail call optimized. -Fred -- Science answers questions; philosophy questions answers. On Aug 2, 2010, at 4:09 PM, Dale wrote: The JVM has an unconditional goto opcode and the ability to re-bind function parameters, so why no tail-call optimization? Thanks. Dale -- 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.comclojure%2bunsubscr...@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.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- 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.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- Daniel Kersten. Leveraging dynamic paradigms since the synergies of 1985. -- 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
Running on .Net
I have a 3rd party platform I am working to write add-ons for and so am restricted to .Net. I'd like to write in Clojure. ClojureCLR looked too intimidating to get it going and ikvmc was very easy for Java, so I thought I'd try it with Clojure. I ran ikvmc on clojure.jar and saw a number of errors (or something), but ignored them, and it did create clojure.dll. I ran ikvmc on my own .class files that were generated by the compile macro. Trying to call a method on my class (with clojure.dll referenced) resulted in: Unhandled Exception: System.TypeInitializationException: The type initializer fo r 'test.clojure.MyClass' threw an exception. --- System.TypeInitializationExcep tion: The type initializer for 'clojure.lang.RT' threw an exception. --- java.l ang.RuntimeException: java.io.FileNotFoundException: Could not locate clojure/co re__init.class or clojure/core.clj on classpath: --- End of inner exception stack trace --- at clojure.lang.Namespace..ctor(Symbol ) at clojure.lang.Namespace.findOrCreate(Symbol name) at clojure.lang.Var.internPrivate(String nsName, String sym) at test.clojure.MyClass..cctor() --- End of inner exception stack trace --- at test.clojure.MyClass.main(String[] strarr) at StartupCode$FSTestApp.$Mentics.Series.App.main@() in C:\Users \jshellman\ Documents\Visual Studio 2008\Projects\FSTestForNT\FSTestApp \Mentics.Series.App.f s:line 14 -- 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
2 links for beginners
as a beginner i found 2 links that i can recommend to others who want to step into matter: 1. mark volkmann's article about clojure: http://java.ociweb.com/mark/clojure/article.html this is a first class introduction to clojure and you can read through it in 2-3 days. it contains everything a typical beginner need to know and i think that in some respects marks article is even better organized than 'programming clojure' or 'the joy of clojure' -- both are excellent books though and can be recommended for reading after marks article. 2. an article to read after 1. IMO that is useful as an antitoxin for beginners: http://imagine27.com/articles/2009-08-19-011225_clojure_the_false_lisp.html because excitement is always a bad thing ... isn't it ? -- 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: Why no tail call optimization
On Aug 3, 2:19 am, Daniel Kersten dkers...@gmail.com wrote: Can one not detect that a recursive call is a tail call and then transform the AST so that its iterative instead - ie, not use the stack besides for initial setup of local variables (which then get reused in each recursive tail-call). Isn't this how its done in native compiled languages with TCO? How is this different from generating bytecode for iterative loops in imperative languages, or from what recur does? Alternatively, why can't the tail call be detected and converted into recur? I'm guessing that the problem is detecting tal calls - but why; speed of dynamic compilation? Something else? Obviously I'm missing something fundamental here - can somebody explain to me what it is? When speaking about general TCO, we are not just talking about recursive self-calls, but also tail calls to other functions. Full TCO in the latter case is not possible on the JVM at present whilst preserving Java calling conventions (i.e without interpreting or inserting a trampoline etc). While making self tail-calls into jumps would be easy (after all, that's what recur does), doing so implicitly would create the wrong expectations for those coming from, e.g. Scheme, which has full TCO. So, instead we have an explicit recur construct. Essentially it boils down to the difference between a mere optimization and a semantic promise. Until I can make it a promise, I'd rather not have partial TCO. Some people even prefer 'recur' to the redundant restatement of the function name. In addition, recur can enforce tail-call position. 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: Why no tail call optimization
Interestingly, [Erjang][1] (a port of Erlang to the JVM) apparently performs TCO while claiming to stay reasonably fast. The gimmick I have never done extensive benchmarking of clojure, but given the frequent mentions of use of '-server' in order to achieve specific performance goals, I get the impression clojure (i.e. Rich) definitely wants to take advantage of all the optimizations the JIT can offer now and in the future. Trampoline-based TCO would, as far as I can tell, always defeat the JIT's notion of a call site - unless the JIT is made to understand the trampoline (but then are we getting close to full TCO support anyway? I dunno, I'm definitely not an expert on this topic...). So, I would expect that those cases which are aggressively optimized by JIT:ing, such as eliminating method lookups by inline caching in light loops, would suffer potentially very extreme performance impacts which aren't fixed by just avoiding allocation as is mentioned in the erjang wiki page. Or is this over-stating the problem? -- / 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: Running on .Net
I've gotten ClojureCLR running on .NET. If you're interested in trying it, ping me and I'll help with what I can. I'm also interested to know if there's some kind of installer or package provided for it yet because as you say it does take a bit to setup. I'd be eager to help in that area if there's interest. On 3 August 2010 09:16, taotree jshell...@gmail.com wrote: I have a 3rd party platform I am working to write add-ons for and so am restricted to .Net. I'd like to write in Clojure. ClojureCLR looked too intimidating to get it going and ikvmc was very easy for Java, so I thought I'd try it with Clojure. I ran ikvmc on clojure.jar and saw a number of errors (or something), but ignored them, and it did create clojure.dll. I ran ikvmc on my own .class files that were generated by the compile macro. Trying to call a method on my class (with clojure.dll referenced) resulted in: Unhandled Exception: System.TypeInitializationException: The type initializer fo r 'test.clojure.MyClass' threw an exception. --- System.TypeInitializationExcep tion: The type initializer for 'clojure.lang.RT' threw an exception. --- java.l ang.RuntimeException: java.io.FileNotFoundException: Could not locate clojure/co re__init.class or clojure/core.clj on classpath: --- End of inner exception stack trace --- at clojure.lang.Namespace..ctor(Symbol ) at clojure.lang.Namespace.findOrCreate(Symbol name) at clojure.lang.Var.internPrivate(String nsName, String sym) at test.clojure.MyClass..cctor() --- End of inner exception stack trace --- at test.clojure.MyClass.main(String[] strarr) at StartupCode$FSTestApp.$Mentics.Series.App.main@() in C:\Users \jshellman\ Documents\Visual Studio 2008\Projects\FSTestForNT\FSTestApp \Mentics.Series.App.f s:line 14 -- 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: Clojure Job Opportunity
This position does offer a possible sponsership of a visa. However, the candidate applying would have to be a perfect fit. If interested please send a resume and a sample of some clojure code (blog or bitbucket) to jack.kenn...@avidtr.com. If our client thinks your skills are worth the expense of sponsership it will not be an issue. Thanks! On Aug 3, 12:04 am, fin gpl...@gmail.com wrote: Can a person outside US apply? On Aug 3, 6:44 am, Jack_Kennedy - AVID jkennedy1...@gmail.com wrote: Looking for a Senior Software Engineer with experience working with Clojure to join a fantastic company in the Boston area. This person will be responsible for designing and developing next generation software for the purpose of delivering mobile content running on a large network of servers. If interested please call me at 617-951-1891. Relocation is offered for this position.- Hide quoted text - - Show quoted text - -- 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: 2 links for beginners
That is the most unsubstantiated, moronic piece of writing I've ever read in my life. I can't really tell what he's attacking, he's just swinging some dick-shaped sword around trying to hit stuff. -Fred -- Science answers questions; philosophy questions answers. On Aug 3, 2010, at 6:30 AM, faenvie wrote: 2. an article to read after 1. IMO that is useful as an antitoxin for beginners: http://imagine27.com/articles/2009-08-19-011225_clojure_the_false_lisp.html because excitement is always a bad thing ... isn't it ? -- 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: 2 links for beginners
The artical is really good for people you like to jump in headfirst. I'm more of a book first guy but I told my, soon to be Clojure Programmer :) , friend about that article. Thats why nobody likes (liked) the Lisp compunity. Read the Comments http://www.loper-os.org/?p=42 On Aug 3, 4:05 pm, Frederick Polgardy f...@polgardy.com wrote: That is the most unsubstantiated, moronic piece of writing I've ever read in my life. I can't really tell what he's attacking, he's just swinging some dick-shaped sword around trying to hit stuff. -Fred -- Science answers questions; philosophy questions answers. On Aug 3, 2010, at 6:30 AM, faenvie wrote: 2. an article to read after 1. IMO that is useful as an antitoxin for beginners: http://imagine27.com/articles/2009-08-19-011225_clojure_the_false_lis... because excitement is always a bad thing ... isn't it ? -- 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: bugs in with-local-vars and lexically-nested-function access to outer function parameters
Defining function (with defn) inside another function isn't very beautiful (def* outside of the top-level is generally disregarded). It looks like you use thhelp only inside the thsolve-function. Use either letfn or (let [thhelp (fn )] ...) here. On Tue, Aug 3, 2010 at 5:07 AM, Mark Engelberg mark.engelb...@gmail.com wrote: Can you distill this down to the smallest possible example that demonstrates the error? -- 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 -- Moritz Ulrich Programmer, Student, Almost normal Guy http://www.google.com/profiles/ulrich.moritz -- 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
small gotcha with the helpfile of empty? / seq?
Occasionally, I want to map a collection of seqs to their is-empty or is-not-empty status (e.g. true / false). And the helpfile of empty? puts me on the wrong leg occasionally. clojure.core/ empty? ([coll]) Returns true if coll has no items - same as (not (seq coll)). Please use the idiom (seq x) rather than (not (empty? x)) If I decide I specifically want true or false returned, and not (content of seq) / false, I sometimes pick up seq?, not realizing that it will always return true on both empty and filled seqs. Made the mistake a few times so far, and I blame it on this helpfile putting me on the wrong leg :-). Perhaps we could add a short line after the last saying , unless you specifically need true/false returned, rather than content/false. -- 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: Running on .Net
I really wish that ClojureCLR had a binary distribution. I like clojure a lot but I have a .Net background and a lot of .Net code to interact with. If ClojureCLR had a stable, dependable binary distribution I would be able to use it at work much more than I already do. I don't care much about 1.2 features like defrecord. What I care about is start-up speed, ease of embeddability, and Visual Studio integration (not Intellisense, just AOT'ing .clj files). On Aug 3, 7:30 am, Hadi Hariri hadihar...@gmail.com wrote: I've gotten ClojureCLR running on .NET. If you're interested in trying it, ping me and I'll help with what I can. I'm also interested to know if there's some kind of installer or package provided for it yet because as you say it does take a bit to setup. I'd be eager to help in that area if there's interest. On 3 August 2010 09:16, taotree jshell...@gmail.com wrote: I have a 3rd party platform I am working to write add-ons for and so am restricted to .Net. I'd like to write in Clojure. ClojureCLR looked too intimidating to get it going and ikvmc was very easy for Java, so I thought I'd try it with Clojure. I ran ikvmc on clojure.jar and saw a number of errors (or something), but ignored them, and it did create clojure.dll. I ran ikvmc on my own .class files that were generated by the compile macro. Trying to call a method on my class (with clojure.dll referenced) resulted in: Unhandled Exception: System.TypeInitializationException: The type initializer fo r 'test.clojure.MyClass' threw an exception. --- System.TypeInitializationExcep tion: The type initializer for 'clojure.lang.RT' threw an exception. --- java.l ang.RuntimeException: java.io.FileNotFoundException: Could not locate clojure/co re__init.class or clojure/core.clj on classpath: --- End of inner exception stack trace --- at clojure.lang.Namespace..ctor(Symbol ) at clojure.lang.Namespace.findOrCreate(Symbol name) at clojure.lang.Var.internPrivate(String nsName, String sym) at test.clojure.MyClass..cctor() --- End of inner exception stack trace --- at test.clojure.MyClass.main(String[] strarr) at StartupCode$FSTestApp.$Mentics.Series.App.main@() in C:\Users \jshellman\ Documents\Visual Studio 2008\Projects\FSTestForNT\FSTestApp \Mentics.Series.App.f s:line 14 -- 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: Records can't be treated as functions anymore
Hi BG, It is a common mistake to think that callability, corresponding to the clojure.lang.IFn interface, is part of the persistent map contract (I've done it myself, as did many others a Conj labs :). It is not. It is actually just a feature of clojure.lang.PersistentHashMap (and the other clojure map implementations). While I get that part, I wonder why records do not implement IFn, it'd be convenient if they did. -- 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
Keywords as enumerations
Hi, In The Joy of Clojure book, it is mentioned Very often Clojure code will use keywords as enumerations: :small :medium :large. What does this mean? thanks -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Keywords as enumerations
I think enumeration here refers to a given number of possible choices Here, it refers to a size, that can be one of the three (:small, :medium, :large). The choices are known in advance and in finite number. It is a traditional way of describing that, that is at least as old as C's enum. (I am not old enough to track the notion further) On Tue, Aug 3, 2010 at 6:37 PM, vishy vishalsod...@gmail.com wrote: Hi, In The Joy of Clojure book, it is mentioned Very often Clojure code will use keywords as enumerations: :small :medium :large. What does this mean? thanks -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- 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
= and byte arrays
Given two byte arrays that have the same content (value) the code below runs without errors: (def ba1 (...)) (def ba2 (...)) (assert (not= ba1 ba2)) (assert (= (String. ba1) (String ba2))) Is this as expected? -- 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: 2 links for beginners
On Tue, 3 Aug 2010 07:28:39 -0700 (PDT) nickikt nick...@gmail.com wrote: The artical is really good for people you like to jump in headfirst. I'm more of a book first guy but I told my, soon to be Clojure Programmer :) , friend about that article. Thats why nobody likes (liked) the Lisp compunity. Read the Comments http://www.loper-os.org/?p=42 Even LISPers: http://steve-yegge.blogspot.com/2006/04/lisp-is-not-acceptable-lisp.html mike -- Mike Meyer m...@mired.org 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: Keywords as enumerations
Should probably have been written as enumeration values (and not solely as enumerations). 2010/8/3 vishy vishalsod...@gmail.com Hi, In The Joy of Clojure book, it is mentioned Very often Clojure code will use keywords as enumerations: :small :medium :large. What does this mean? thanks -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.comclojure%2bunsubscr...@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: = and byte arrays
yes, since arrays are mutables, the only equality semantics that's stable over the application timeline is object identity equality. Thus = on arrays is based on java's == 2010/8/3 Steven Devijver steven.devij...@gmail.com Given two byte arrays that have the same content (value) the code below runs without errors: (def ba1 (...)) (def ba2 (...)) (assert (not= ba1 ba2)) (assert (= (String. ba1) (String ba2))) Is this as expected? -- 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.comclojure%2bunsubscr...@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: = and byte arrays
(= (seq ba1) (seq ba2)) will give you a value (byte-by-byte) comparison. On Aug 3, 2:00 pm, Steven Devijver steven.devij...@gmail.com wrote: Given two byte arrays that have the same content (value) the code below runs without errors: (def ba1 (...)) (def ba2 (...)) (assert (not= ba1 ba2)) (assert (= (String. ba1) (String ba2))) Is this as expected? -- 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: dtd question
Hi Randy, On Sun, 1 Aug 2010 15:02:59 -0700 (PDT) Randy Hudson randy_hud...@mac.com wrote: I think we're almost there, sorry for the various mistakes. If you look in the source for clojure.xml, you can see that the default startparse argument for xml/parse is (defn startparse-sax [s ch] (.. SAXParserFactory (newInstance) (newSAXParser) (parse s ch))) and we've only gotten as far as the newSAXParser part with the definition of parser. So: (defn startparse [s ch] (.parse parser s ch)) (defn parse-xml [source] (xml/parse source startparse)) Indeed now it compiles. I also played with startparse but my mistake was to omit the dot in front of parse. For some reasons I do not get it to ignore the DTD but it seems (from Google search) that others had that issue before with EntityResolver. It looks like resolver gets ignored. But I found this Java snippet: SAXParser parser = factory.newSAXParser(); parser.setFeature(http://apache.org/xml/features/nonvalidating/load-external-dtd;, false); This is the code that works now: (ns xmltest (:require [clojure.zip :as zip] [clojure.xml :as xml]) (:use clojure.contrib.zip-filter.xml)) (import '[javax.xml.parsers SAXParserFactory]) (def parser (let [pf (SAXParserFactory/newInstance)] (do (. pf setFeature http://apache.org/xml/features/nonvalidating/load-external-dtd; false) (.newSAXParser pf (defn startparse [s ch] (.parse parser s ch)) (defn parse-xml [source] (xml/parse source startparse)) (parse-xml (java.io.File. test.xml)) Thanks a lot for your help. -- Manfred -- 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
equality of primitive values
Dear all, I am still fighting with a profiler and primitive hints. It seems I cannot manage to have a direct equality check of the primitive. My profiler tells me it goes through clojure.lang.Numbers eq. What is the best way to test equality of unboxed primitive? (The two primitive are of the same primitive type) 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: 2 links for beginners
Fred, That is the most unsubstantiated, moronic piece of writing I've ever read in my life. I can't really tell what he's attacking, he's just swinging some dick-shaped sword around trying to hit stuff. It's OK, it's alright. Naysayers will always have some issue to pick on, and when they don't have any (as in this case), they will resort to such meaningless rants. Let's set an example by completely ignoring such unhelpful yet poisonous people. Regards, BG -- Baishampayan Ghose b.ghose at gmail.com -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
What is #_
Hi, I've read the src of core.clj of Clojure 1.1.0. Originally I thought the meaning of #_ is to comment the thing after it, sort of like `;'. But the in the src of core.clj in 1.2.0-RC1. The definition of reduce is overrided to use the internal-reduce function. The defn line, is preceded by `#_'. But in 1.1.0, it's not preceded by this reader macro. So, I'm confused... -- 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: Running on .Net
For the binary distribution, it's not hard. I could setup a CI project at http://teamcity.codebetter.com and put together some binaries to download. Regarding Stability and speed, it's way too early for me to comment since I'm a newbie with Clojure so I couldn't really comment. On 3 August 2010 18:56, eyeris drewpvo...@gmail.com wrote: I really wish that ClojureCLR had a binary distribution. I like clojure a lot but I have a .Net background and a lot of .Net code to interact with. If ClojureCLR had a stable, dependable binary distribution I would be able to use it at work much more than I already do. I don't care much about 1.2 features like defrecord. What I care about is start-up speed, ease of embeddability, and Visual Studio integration (not Intellisense, just AOT'ing .clj files). On Aug 3, 7:30 am, Hadi Hariri hadihar...@gmail.com wrote: I've gotten ClojureCLR running on .NET. If you're interested in trying it, ping me and I'll help with what I can. I'm also interested to know if there's some kind of installer or package provided for it yet because as you say it does take a bit to setup. I'd be eager to help in that area if there's interest. On 3 August 2010 09:16, taotree jshell...@gmail.com wrote: I have a 3rd party platform I am working to write add-ons for and so am restricted to .Net. I'd like to write in Clojure. ClojureCLR looked too intimidating to get it going and ikvmc was very easy for Java, so I thought I'd try it with Clojure. I ran ikvmc on clojure.jar and saw a number of errors (or something), but ignored them, and it did create clojure.dll. I ran ikvmc on my own .class files that were generated by the compile macro. Trying to call a method on my class (with clojure.dll referenced) resulted in: Unhandled Exception: System.TypeInitializationException: The type initializer fo r 'test.clojure.MyClass' threw an exception. --- System.TypeInitializationExcep tion: The type initializer for 'clojure.lang.RT' threw an exception. --- java.l ang.RuntimeException: java.io.FileNotFoundException: Could not locate clojure/co re__init.class or clojure/core.clj on classpath: --- End of inner exception stack trace --- at clojure.lang.Namespace..ctor(Symbol ) at clojure.lang.Namespace.findOrCreate(Symbol name) at clojure.lang.Var.internPrivate(String nsName, String sym) at test.clojure.MyClass..cctor() --- End of inner exception stack trace --- at test.clojure.MyClass.main(String[] strarr) at StartupCode$FSTestApp.$Mentics.Series.App.main@() in C:\Users \jshellman\ Documents\Visual Studio 2008\Projects\FSTestForNT\FSTestApp \Mentics.Series.App.f s:line 14 -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Running on .Net
I really wish that ClojureCLR had a binary distribution. I like clojure a lot but I have a .Net background and a lot of .Net code to interact with. If ClojureCLR had a stable, dependable binary distribution I would be able to use it at work much more than I already do. I don't care much about 1.2 features like defrecord. What I care about is start-up speed, ease of embeddability, and Visual Studio integration (not Intellisense, just AOT'ing .clj files). +1 for all of that That paragraph basically explains why I haven't started using clojure at my work yet. Timothy Baldridge -- 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
Resource cleanup when lazy sequences are finalized
I want to create a lazy seq backed by an open file (or db connection, or something else that needs cleanup). I can't wrap the consumer in a with-anything. Is there a general method for cleaning up after the consumer discards its reference to that lazy seq? I'm vaguely aware of Java finalize, but am also aware that it is unpredictable (e.g. you aren't guaranteed to be driven at the next gc). Does Clojure even provide the ability to define a finalize method for a lazy seq? (Sipping water from a firehose...) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: What is #_
Hi, Am 03.08.2010 um 16:45 schrieb Yang Dong: I've read the src of core.clj of Clojure 1.1.0. Originally I thought the meaning of #_ is to comment the thing after it, sort of like `;'. But the in the src of core.clj in 1.2.0-RC1. The definition of reduce is overrided to use the internal-reduce function. The defn line, is preceded by `#_'. But in 1.1.0, it's not preceded by this reader macro. So, I'm confused... You are absolutely right. The #_ is kind of comment. And in fact the override with the internal reduce function is commented out (ie. it’s not active) in 1.2. 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: What is #_
#_ comments the whole form, starting with parent just after #_ : #_(bla-bla (bla-bla2 ... ) ) for example (+ #_ (+ 2 3 4 (* 1 2) ) 1 2) Will return 3, because form with (+ 2 3 ... ) will be ignored by reader So it's restricted by 1 line like ; Regards Nikita Beloglazov On Tue, Aug 3, 2010 at 10:35 PM, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 03.08.2010 um 16:45 schrieb Yang Dong: I've read the src of core.clj of Clojure 1.1.0. Originally I thought the meaning of #_ is to comment the thing after it, sort of like `;'. But the in the src of core.clj in 1.2.0-RC1. The definition of reduce is overrided to use the internal-reduce function. The defn line, is preceded by `#_'. But in 1.1.0, it's not preceded by this reader macro. So, I'm confused... You are absolutely right. The #_ is kind of comment. And in fact the override with the internal reduce function is commented out (ie. it’s not active) in 1.2. 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.comclojure%2bunsubscr...@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: What is #_
Sorry, it's NOT restricted by 1 line, like ; :) Regards Nikita Beloglazov On Tue, Aug 3, 2010 at 10:54 PM, Nikita Beloglazov nikelandj...@gmail.comwrote: #_ comments the whole form, starting with parent just after #_ : #_(bla-bla (bla-bla2 ... ) ) for example (+ #_ (+ 2 3 4 (* 1 2) ) 1 2) Will return 3, because form with (+ 2 3 ... ) will be ignored by reader So it's restricted by 1 line like ; Regards Nikita Beloglazov On Tue, Aug 3, 2010 at 10:35 PM, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 03.08.2010 um 16:45 schrieb Yang Dong: I've read the src of core.clj of Clojure 1.1.0. Originally I thought the meaning of #_ is to comment the thing after it, sort of like `;'. But the in the src of core.clj in 1.2.0-RC1. The definition of reduce is overrided to use the internal-reduce function. The defn line, is preceded by `#_'. But in 1.1.0, it's not preceded by this reader macro. So, I'm confused... You are absolutely right. The #_ is kind of comment. And in fact the override with the internal reduce function is commented out (ie. it’s not active) in 1.2. 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.comclojure%2bunsubscr...@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: Running on .Net
I can move creating a binary distribution to the to top of the list. I could use some guidance from the interested on what would serve the purpose on this and other things mentioned here. on the distribution: Do you want just a zip of of DLLs? An installer? Do you want installation to the GAC? on 'stable, dependable': Is there any strategy on creating new releases that makes sense? Assume anyone wanting to stay on the bleeding edge will build for themselves? start-up speed: I'm running some experiments on that. The problem is mostly the monolithic nature of the assemblies created and the amount of environment initialization. Suggestions welcomed. Ease of embeddability: please elaborate on the problems. AOT'ing clj files: Ditto. -David On Aug 3, 12:47 pm, Timothy Baldridge tbaldri...@gmail.com wrote: I really wish that ClojureCLR had a binary distribution. I like clojure a lot but I have a .Net background and a lot of .Net code to interact with. If ClojureCLR had a stable, dependable binary distribution I would be able to use it at work much more than I already do. I don't care much about 1.2 features like defrecord. What I care about is start-up speed, ease of embeddability, and Visual Studio integration (not Intellisense, just AOT'ing .clj files). +1 for all of that That paragraph basically explains why I haven't started using clojure at my work yet. Timothy Baldridge -- 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: Resource cleanup when lazy sequences are finalized
On Tue, Aug 3, 2010 at 3:21 PM, David Andrews dammi...@gmail.com wrote: I want to create a lazy seq backed by an open file (or db connection, or something else that needs cleanup). I can't wrap the consumer in a with-anything. Is there a general method for cleaning up after the consumer discards its reference to that lazy seq? I'm vaguely aware of Java finalize, but am also aware that it is unpredictable (e.g. you aren't guaranteed to be driven at the next gc). Does Clojure even provide the ability to define a finalize method for a lazy seq? (Sipping water from a firehose...) The descriptor(/db connection/etc) will be cleaned up eventually, when the finalizer runs. The problem with this is that you don't know when the finalizer will run, and it can be arbitrarily delayed. So it's possible for a program to run out of file descriptors, if there are file descriptors which are garbage but not yet collected. Another possibility, if you know that the consumer will force the entire list before discarding it, is to concat on a zero-element list which closes the descriptor, like: (concat orig-list (lazy-seq (do (.close fd) []))) On the other hand, the consumer doesn't force the whole list, then the descriptor never gets closed. So the real answer is: this isn't a good use for seqs. It looks like one, but it isn't. 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: Resource cleanup when lazy sequences are finalized
On Aug 3, 4:40 pm, Brian Hurt bhur...@gmail.com wrote: So the real answer is: this isn't a good use for seqs. I was afraid that was the case. Too bad, 'cause seqs are otherwise elegant. Thanks for the sanity check. -- 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: Symbol substitution in macro
On Mon, 2 Aug 2010 07:23:12 -0400 Andrew Boekhoff boekho...@gmail.com wrote: On Sunday 01 August 2010 21:34:16 Kyle Schaffrick wrote: Hello, I'm trying to write a library with two main parts. The first is a macro, I'll call it 'with-feature, that walks through forms passed inside it, and any time it sees a call to another function in my library, 'feature, do some transformations. The problem I'm concerned about is as follows: When my macro sees the forms that are passed into it, the symbols come in however the consumer of the library wrote them. So say I :require my library and alias it to 'mylib', then the call 'with-feature is looking for appears as 'mylib/feature. Or, I could :use the library, and then it would appear as 'feature, or I could alias 'feature to 'banana--you get the idea. I don't want to reserve some magic symbol name that defies namespace rules, so that if the library consumer code uses the symbol 'feature to mean something different, they get bizarre results. What is a good pattern for writing the matching logic in such a selectively-transforming macro so that it can properly find the magic call it's looking for in the presence of normal namespacing behavior? Thanks, -Kyle Hi, The following technique seems to work for finding out if you've been aliased: (ns somewhere.trial) (let [here *ns*] (defmacro whats-my-name [] (some (fn [[k v]] (when (= here v) `(quote ~k))) (ns-aliases *ns* user (require '[somewhere.trial :as aliased]) = user (aliased/whats-my-name) = aliased So at the top of with-feature the parser could check for an alias and construct the appropriate predicate from the result. -Andy I originally had something similar to this actually, but it doesn't work for the case when the library is referred in the consumer code with :use because the symbol's namespace is then nil, and you still can't tell if they're shadowing it with a let binding, or have renamed it with :as. However, this idea occurred to me yesterday. What if I check to see if the symbol is pointing to the *var* containing my magic function, instead of trying to examine the symbol itself? e.g.: (= (resolve symbol-i-am-scanning-in-my-macro) #'function-i-am-looking-for) It seems to work, since at macro-expand time *ns* is bound to the consumer code's namespace. Does this seem like a reasonable way to deal with this? -Kyle -- 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: Why no tail call optimization
When speaking about general TCO, we are not just talking about recursive self-calls, but also tail calls to other functions. Full TCO in the latter case is not possible on the JVM at present whilst preserving Java calling conventions (i.e without interpreting or inserting a trampoline etc). Understood. Thanks! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Time and FRP
Hello! I have bit vague question is ( and if how..) Clojure model of value/ state/identity related to the problem described here: http://pchiusano.blogspot.com/2010/07/reification-of-time-in-frp-is.html ? thanks, regards andreas -- 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: bugs in with-local-vars and lexically-nested-function access to outer function parameters
On Aug 2, 11:07 pm, Mark Engelberg mark.engelb...@gmail.com wrote: Can you distill this down to the smallest possible example that demonstrates the error? Nope. Just spent some time trying to duplicate the nested function bug in a simpler context. A pointer to the place where I should deposit code that manifests a run-time bug in Clojure would be the thing here. Code that reliably exposes underlying bugs is like money in the bank. -- 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: bugs in with-local-vars and lexically-nested-function access to outer function parameters
On Aug 3, 11:26 am, Moritz Ulrich ulrich.mor...@googlemail.com wrote: Defining function (with defn) inside another function isn't very beautiful (def* outside of the top-level is generally disregarded). It looks like you use thhelp only inside the thsolve-function. Use either letfn or (let [thhelp (fn )] ...) here. This statement is ironic, considering the definition of a functional closure, after which Clojure is presumably named. From http://en.wikipedia.org/wiki/Closure_%28computer_science%29 In some languages, a closure may occur when a function is defined within another function, and the inner function refers to local variables of the outer function. At runtime, when the outer function executes, a closure is formed, consisting of the inner function’s code and references to any variables of the outer function required by the closure; such variables are called the upvalues of the closure. I haven't had an application for returning closures as first class objects (yet), but presumably, if Clojure supports first-class functions (see http://clojure.org/functional_programming) and allows nested function definitions with lexical scope, then it supports closures. -- 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: Running on .Net
Personally I'd like to see it in a .zip of assemblies. GAC can make it a bit hard to copy around...90% of my 3rd party assemblies, I just throw in a folder and reference in VC# where they get copied into the build directory. Unfortunately, I haven't gotten ClojureCLR to compile, so I can't speak to the startup times. For the most part, a 1-2 sec startup isn't bad in my book though. Timothy -- 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: Resource cleanup when lazy sequences are finalized
See my library at http://github.com/jpalmucci/clj-yield, which makes this trivial. For example, here is a function I use to read a sequence of java serialized objects from a stream: (defn read-objects [path] (with-yielding [out 1000] (with-open [stream (java.io.ObjectInputStream. (java.io.BufferedInputStream. (java.util.zip.GZIPInputStream. (java.io.FileInputStream. (io/file path)] (loop [] (try (let [next (.readObject stream)] (yield out next) (recur)) (catch java.io.EOFException e (.close stream))) When the sequence returned by with-yielding becomes garbage collectable, yield will throw an exception causing with-open to close the file. Note that with-yielding will use a thread from the thread pool, so its a bad idea to have hundreds of active with-yieldings at once. On Aug 3, 3:21 pm, David Andrews dammi...@gmail.com wrote: I want to create a lazy seq backed by an open file (or db connection, or something else that needs cleanup). I can't wrap the consumer in a with-anything. Is there a general method for cleaning up after the consumer discards its reference to that lazy seq? I'm vaguely aware of Java finalize, but am also aware that it is unpredictable (e.g. you aren't guaranteed to be driven at the next gc). Does Clojure even provide the ability to define a finalize method for a lazy seq? (Sipping water from a firehose...) -- 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: Why no tail call optimization
Thanks for the replies, that certainly clarified things! On 3 August 2010 13:39, Rich Hickey richhic...@gmail.com wrote: On Aug 3, 2:19 am, Daniel Kersten dkers...@gmail.com wrote: Can one not detect that a recursive call is a tail call and then transform the AST so that its iterative instead - ie, not use the stack besides for initial setup of local variables (which then get reused in each recursive tail-call). Isn't this how its done in native compiled languages with TCO? How is this different from generating bytecode for iterative loops in imperative languages, or from what recur does? Alternatively, why can't the tail call be detected and converted into recur? I'm guessing that the problem is detecting tal calls - but why; speed of dynamic compilation? Something else? Obviously I'm missing something fundamental here - can somebody explain to me what it is? When speaking about general TCO, we are not just talking about recursive self-calls, but also tail calls to other functions. Full TCO in the latter case is not possible on the JVM at present whilst preserving Java calling conventions (i.e without interpreting or inserting a trampoline etc). Ah, this where my confusion was then. Self-calls aren't the problem at all, since they can be compiled how recur is, but tail-calls to other functions cannot be due to the JVM's calling conventions. I understand now, thanks for the explanation. While making self tail-calls into jumps would be easy (after all, that's what recur does), doing so implicitly would create the wrong expectations for those coming from, e.g. Scheme, which has full TCO. So, instead we have an explicit recur construct. Essentially it boils down to the difference between a mere optimization and a semantic promise. Until I can make it a promise, I'd rather not have partial TCO. To me, it is really only an optimization and I'm very much in the group who likes the explicit recur statement, since it conveys intent. Therefore I'd be happy with the partial optimization, though, honestly, not having it doesn't bother me at all. Some people even prefer 'recur' to the redundant restatement of the function name. In addition, recur can enforce tail-call position. 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.comclojure%2bunsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en -- Daniel Kersten. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: What is #_
Thank you! I have just another question not related about this topic:
;during bootstrap we don't have destructuring let, loop or fn, will
redefine later
(def
^{:macro true
:added 1.0}
let (fn* let [form env decl] (cons 'let* decl)))
In Clojure 1.2.0, the preceding definition of let taks the strange
argument of `form' and `env'. What are they?
On Aug 4, 3:35 am, Meikel Brandmeyer m...@kotka.de wrote:
Hi,
Am 03.08.2010 um 16:45 schrieb Yang Dong:
I've read the src of core.clj of Clojure 1.1.0. Originally I thought
the meaning of #_ is to comment the thing after it, sort of like `;'.
But the in the src of core.clj in 1.2.0-RC1. The definition of reduce
is overrided to use the internal-reduce function. The defn line, is
preceded by `#_'. But in 1.1.0, it's not preceded by this reader
macro. So, I'm confused...
You are absolutely right. The #_ is kind of comment. And in fact the override
with the internal reduce function is commented out (ie. it’s not active) in
1.2.
Sincerely
Meikel
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Re: bugs in with-local-vars and lexically-nested-function access to outer function parameters
On Tue, Aug 3, 2010 at 1:06 PM, Dale dpar...@ptd.net wrote: This statement is ironic, considering the definition of a functional closure, after which Clojure is presumably named. You're missing the point. A defn inside another defn doesn't do what you think it does. defn always creates a global variable, even when it looks like it should create a local. You can create closures, but you should use letfn instead. -- 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: bugs in with-local-vars and lexically-nested-function access to outer function parameters
On Tue, Aug 3, 2010 at 1:00 PM, Dale dpar...@ptd.net wrote: On Aug 2, 11:07 pm, Mark Engelberg mark.engelb...@gmail.com wrote: Can you distill this down to the smallest possible example that demonstrates the error? Nope. Just spent some time trying to duplicate the nested function bug in a simpler context. Well if you can't duplicate the bug in a simpler context, it seems more likely that the bug is in the logic of your code, or your understanding of these constructs, doesn't it? Your example is long enough I only had time to glance briefly at it. Based on what I could glean from that quick look, I think you may have a misunderstanding about how with-local-vars works. vars are thread-specific, and they have a lifetime that is delimted by dynamic scoping rather than lexical scoping. Using vars in conjunction with futures seems like a recipe for disaster. A null pointer exception would be not at all surprising to me in this context, because the var goes away when the block of code that created it exits. I generally advise people to stay away from vars unless they know exactly what they are doing. Vars have all sorts of unintuitive interactions with laziness and multithreading. Try refactoring your algorithm in a way that doesn't need mutable locals. If you absolutely do need a mutable local, just use an atom. -- 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: bugs in with-local-vars and lexically-nested-function access to outer function parameters
Similarly, don't use def inside of a defn. Use let. On Tue, Aug 3, 2010 at 9:10 PM, Mark Engelberg mark.engelb...@gmail.comwrote: On Tue, Aug 3, 2010 at 1:06 PM, Dale dpar...@ptd.net wrote: This statement is ironic, considering the definition of a functional closure, after which Clojure is presumably named. You're missing the point. A defn inside another defn doesn't do what you think it does. defn always creates a global variable, even when it looks like it should create a local. You can create closures, but you should use letfn instead. -- 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: Why no tail call optimization
Some people even prefer 'recur' to the redundant restatement of the function name. In addition, recur can enforce tail-call position. Rich Because recur only takes you back to the innermost loop, sometimes I miss the ability to jump back to some outer loop (or the overall function call). Hypothetically, could Clojure support a way to name a specific loop, and use a version of recur that lets you jump back to a given named outer loop (like Scheme's named let), or is this outside the scope of what Java's goto permits? -- 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: Running on .Net
I would like a zip of DLLs that are as widely compatible as possible across CLR/DLR versions accompanied by a clear list of which versions are compatible. Regarding releases, I'm glad to lag behind the bleeding edge by a lot in order to have a stable platform. What I want to be able to do is grab the DLLs, add them as references to my VS project, and compile, much like I do with NetBeans and the JVM clojure. I have to admit that I haven't tried ClojureCLR since right around the 1.1 release, so I don't remember the details of the problems that I encountered. I am in the process of migrating a lot of stuff from VS 2008 to VS 2010. Once I finish that I will try ClojureCLR again and get back to you regarding embedding and AOT. On Aug 3, 3:11 pm, dmiller dmiller2...@gmail.com wrote: I can move creating a binary distribution to the to top of the list. I could use some guidance from the interested on what would serve the purpose on this and other things mentioned here. on the distribution: Do you want just a zip of of DLLs? An installer? Do you want installation to the GAC? on 'stable, dependable': Is there any strategy on creating new releases that makes sense? Assume anyone wanting to stay on the bleeding edge will build for themselves? start-up speed: I'm running some experiments on that. The problem is mostly the monolithic nature of the assemblies created and the amount of environment initialization. Suggestions welcomed. Ease of embeddability: please elaborate on the problems. AOT'ing clj files: Ditto. -David On Aug 3, 12:47 pm, Timothy Baldridge tbaldri...@gmail.com wrote: I really wish that ClojureCLR had a binary distribution. I like clojure a lot but I have a .Net background and a lot of .Net code to interact with. If ClojureCLR had a stable, dependable binary distribution I would be able to use it at work much more than I already do. I don't care much about 1.2 features like defrecord. What I care about is start-up speed, ease of embeddability, and Visual Studio integration (not Intellisense, just AOT'ing .clj files). +1 for all of that That paragraph basically explains why I haven't started using clojure at my work yet. Timothy Baldridge -- 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
Keywords also have a literal syntax
What does it mean? Does it mean that :hello itself is a value,so we call it literal syntax.Also, this form of vector [1 2 3] is also literal syntax. -- 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: Keywords also have a literal syntax
On Wed, Aug 4, 2010 at 1:33 AM, vishy vishalsod...@gmail.com wrote: What does it mean? Does it mean that :hello itself is a value,so we call it literal syntax.Also, this form of vector [1 2 3] is also literal syntax. A vector evaluates all of its arguments. If I write [1 2 (+ 1 2)], I'll get the same vector you got with [1 2 3]. Keywords always evaluate to themselves. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: What is #_
Hi,
On Aug 4, 2:32 am, Yang Dong ydong.pub...@gmail.com wrote:
Thank you! I have just another question not related about this topic:
;during bootstrap we don't have destructuring let, loop or fn, will
redefine later
(def
^{:macro true
:added 1.0}
let (fn* let [form env decl] (cons 'let* decl)))
In Clojure 1.2.0, the preceding definition of let taks the strange
argument of `form' and `env'. What are they?
user= (defmacro foo [x y] (prn form) (prn env) `(+ ~x ~y))
#'user/foo
user= (let [x 5] (foo x 6))
(foo x 6)
{x #LocalBinding clojure.lang.compiler$localbind...@13f991}
11
form contains the form how the macro was called. env contains local
bindings in the macro environment. (At least this is what my little
test shows...) These magic parameters are given to all parameters, but
usually hidden. It's probably safe to ignore them if you don't know
what they really do.
Sincerely
Meikel
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