Re: minor pauses
Perhaps I'm not reading the GC logging information correctly, but it didn't appear to me that the GC was to blame for the pauses. Perhaps it might not even be the JVM but the OS kernel? Until I have a good idea what's causing them, it seems that throwing solutions (such as moving to a realtime VM) is just stabbing at the dark. From your GC logs it doesn't look like GC is the problem no so for now the point is moot. However, if you are targeting 10 ms pause times you may or may not at some point have a problem. For very small heap sizes and moderate allocation rates it'll probably work okay. Once you start having larger heap sizes or lots of allocation, it becomes more difficult. Depending on your application, it may or may not be an issue. Just be aware that there is no expectation that CMS will *guarantee* you 10 ms pause times. Same for G1 (or JRockit for that matter). As for discovering the real cause of the pause: Without obvious culprits I would probably just do a binary search of source, in terms of the call stack. Keeping doing the timings at different places and see where you're not seeing the pauses and where you are seeing them, and drill down. Another option, depending on how fast 'jstack' is in relation to your pauses, is to try to get a 'jstack' on the process while you're seeing a pause and see if there is a thread blocking in an unexpected location. That's assuming there is something blocking for an extended period of time that is causing it. -- / 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: help--reading keyboard input from Clojure is surprisingly difficult
On Apr 8, 2011, at 11:33 PM, Gregg Williams wrote: ... *How* does the word easier belong in that sentence, when I all I want to do is read input from the keyboard?! My modest proposal: ... I'm writing to support the sentiment that Gregg expressed here with regard to this issue, and also his broader proposal. List members offered several clever and helpful workarounds in response to Gregg's post, along with pointers to the reasons for the current situation. Great! But still, I will humbly submit that it's totally freakin' nutso that it should be so hard to do basic user interaction. FWIW I looked back at materials I used to teach clojure last semester and saw that I presented some stuff based on read-line in the REPL and it must have worked in the environment that I was using at the time, which was Eclipse/CCW on a mac. But now I do remember that some students who were using this for simple text adventure games had problems, although I don't remember the details. They may have been using other platforms. In any event I will include the code that I shared with the students at that time below... yes, I know that some of you will think that I shouldn't have used eval, etc., but for the purpose I think it was fine and my view that stuff like this should work without clever workarounds in any Clojure environment that isn't labeled as broken. -Lee (ns commandline) (defn read-and-do-line Get from the user and execute a command line without parentheses, where the first thing on the line is the name of a function and the rest of the line is arguments (which will not be evaluated). [] (print command: ) (flush) (let [line (read-line) list-of-things (read-string (str ( line )))] (apply (eval (first list-of-things)) (rest list-of-things (defn inc-and-print [number] (println (inc number))) ;; just an example command to call (defn list-and-print [ args] (println (apply list args))) ;; another (def in-loop (atom false)) ;; just to control the command loop below (defn quit [] (reset! in-loop false)) ;; a function to get out of the loop (defn command-loop [] (reset! in-loop true) (loop [] (when @in-loop (read-and-do-line) (recur ;; 1:3 commandline= (command-loop) ;; command: inc-and-print 3 ;; 4 ;; command: list-and-print :a :b :c 1 2 3 ;; (:a :b :c 1 2 3) ;; command: quit ;; nil ;; 1:7 commandline= -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: Announcement: pretzel - a predicate library + call for suggestions
On 8 April 2011 23:21, Ken Wesson kwess...@gmail.com wrote: Better yet: maybe we're looking at this backwards. Maybe what we want isn't a predicate for *passed* validation, but a predicate for *failed* validation: (defn s-blank? [x] (if (empty? (.trim x)) must not be blank)) That particular example ties a predicate to a particular error message. Error messages should be independent of predicates, otherwise they can't be localized or changed to fit a specific situation. This takes advantage of the fact that the error messages we want are all truthy. It's also the case that you often want to detect and handle invalid input right away, then get to the meat of the logic. The natural ordering of if, if-let, etc. puts the true case first. Making the true case the error case lets you easily get it out of the way first in your code. This would lead to a lot of validations with not in front of them. i.e not-email-address?, not-integer?, etc. - James -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Announcement: pretzel - a predicate library + call for suggestions
On Sat, Apr 9, 2011 at 9:56 AM, James Reeves jree...@weavejester.com wrote: On 8 April 2011 23:21, Ken Wesson kwess...@gmail.com wrote: Better yet: maybe we're looking at this backwards. Maybe what we want isn't a predicate for *passed* validation, but a predicate for *failed* validation: (defn s-blank? [x] (if (empty? (.trim x)) must not be blank)) That particular example ties a predicate to a particular error message. Error messages should be independent of predicates, otherwise they can't be localized or changed to fit a specific situation. It can always be an integer or a keyword (or a string!) used to look up the localized or situation-specific message in a map. This takes advantage of the fact that the error messages we want are all truthy. It's also the case that you often want to detect and handle invalid input right away, then get to the meat of the logic. The natural ordering of if, if-let, etc. puts the true case first. Making the true case the error case lets you easily get it out of the way first in your code. This would lead to a lot of validations with not in front of them. i.e not-email-address?, not-integer?, etc. So? -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: Where is the javadoc for clojure.lang ?
Unfortunately, there is no JavaDoc for clojure.lang because there are no comments in the source. If you want to understand Clojure's Java source code, you'll just have to read it. -Stuart Sierra clojure.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: Where is the javadoc for clojure.lang ?
Also, there is the Clojure in Small Pieces doc that Tim Daly is working on. On Sat, Apr 9, 2011 at 11:00 AM, Stuart Sierra the.stuart.sie...@gmail.comwrote: Unfortunately, there is no JavaDoc for clojure.lang because there are no comments in the source. If you want to understand Clojure's Java source code, you'll just have to read it. -Stuart Sierra clojure.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 -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
ANN: Logos v0.6 - Pattern matching, Tabling, Disequality Constraints, and now on Clojars
Logos is finally in good enough shape to be worth publishing to Clojars. There are really too many changes to enumerate here, but if you're familiar with Prolog, Logos is now far enough along that you can basically write Prolog in Clojure and then some. Here's the evidence: (defn-e nqueens-o [l] ([()]) ([[[?x ?y] . ?others]] (exist [] (nqueens-o ?others) (member-o ?y [1 2 3 4 5 6 7 8]) (noattack-o [?x ?y] ?others (defn-e noattack-o [q others] ([_ ()]) ([[?x ?y] [[?x1 ?y1] . ?others]] (exist [] (!= ?y ?y1) (nonrel/project [?y ?y1 ?x ?x1] (!= (- ?y1 ?y) (- ?x1 ?x)) (!= (- ?y1 ?y) (- ?x ?x1))) (noattack-o [?x ?y] ?others The big changes are: * Pattern matching * Goals can be tabled a la XSB * Fairly efficient implementation of disequality constraints (and programs w/o constraints are not penalized) I've been begun porting some examples from Bratko's excellent Prolog book as a guide for those who are interested here https://github.com/swannodette/bratko-logos. A note on performance: when the search space is not small Logos doesn't perform as well as Prolog since it uses an interleaving strategy, and this interleaving is currently implemented via liberal thunking. While I'm interested in making Logos faster, I think many of the kinds of search problems that are currently slower in Logos than in Prolog are best solved with Constraint Logic Programming anyhow - which is the next major feature for Logos. Enjoy, David -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
How to access specific java.awt.Color constructor?
Hi, I'm trying to create a java.awt.Color class instance from within Clojure, using this constructor: Color(ColorSpace cspace, float[] components, float alpha) But always end up with a No matching ctor found for class java.awt.Color exception. I can create the ColorSpace instance as I expected, but I think I'm missing something with the rest of the Color constructor. I've tried changing the components to a vector of floats or a Java array of floats with no luck. This is with Clojure 1.2 and the Java Platform SE 6 AWT classes. Any advice much appreciated. Stu -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: help--reading keyboard input from Clojure is surprisingly difficult
On Sat, Apr 9, 2011 at 6:46 AM, Lee Spector lspec...@hampshire.edu wrote: But still, I will humbly submit that it's totally freakin' nutso that it should be so hard to do basic user interaction. I'm curious as to what percentage of developers are writing console-based applications (in any language)? What do the processes look like in other languages? How are those processes different to what happens with Clojure? With the following test program, t.clj... (println Testing...) (let [a (read-line)] (println a)) ...I can open up a REPL, do (load-file t.clj) and it runs as expected. I can also type clj run t.clj and it works just fine (can't remember where I got that script from - it just wraps the java command to start Clojure). Now, I will concede that lein run t.clj does not work - and that does seem a bit odd given that lein repl then (load-file t.clj) works but if it's a technical limitation with the run task, fair enough. However, given the clj run command, I can add a #! line to my Clojure scripts, make them execute and just run them: #!/usr/bin/env clj run (println Testing...) (let [a (read-line)] (println a)) Now I can just type ./t.clj and it works as expected... -- Sean A Corfield -- (904) 302-SEAN An Architect's View -- http://corfield.org/ World Singles, LLC. -- http://worldsingles.com/ Railo Technologies, Inc. -- http://www.getrailo.com/ Perfection is the enemy of the good. -- Gustave Flaubert, French realist novelist (1821-1880) -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to access specific java.awt.Color constructor?
Can you show a bit more of the code you have so we can see what you've tried? On Sat, Apr 9, 2011 at 3:13 PM, stu stuart.hungerf...@gmail.com wrote: I'm trying to create a java.awt.Color class instance from within Clojure, using this constructor: Color(ColorSpace cspace, float[] components, float alpha) But always end up with a No matching ctor found for class java.awt.Color exception. I can create the ColorSpace instance as I expected, but I think I'm missing something with the rest of the Color constructor. I've tried changing the components to a vector of floats or a Java array of floats with no luck. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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 to access specific java.awt.Color constructor?
You probably weren't putting it into a java float array, but instead a Float array (boxed type). Here's a repl session doing what you want. I don't know anything about colorspaces so it's probably nonsense, but it creates a Color with that constructor. user= (import '(java.awt.color ICC_Profile ColorSpace ICC_ColorSpace) java.awt.Color) java.awt.Color user= (def prf (ICC_Profile/getInstance (ColorSpace/CS_sRGB))) #'user/prf user= (def spc (ICC_ColorSpace. prf)) #'user/spc user= (class spc) java.awt.color.ICC_ColorSpace ;; the magic words user= (def c (Color. spc (float-array [1 1 1]) (float 1))) #'user/c user= (def c (Color. spc (into-array Float/TYPE [1 1 1]) (float 1))) #'user/c On Apr 9, 3:21 pm, Sean Corfield seancorfi...@gmail.com wrote: Can you show a bit more of the code you have so we can see what you've tried? On Sat, Apr 9, 2011 at 3:13 PM, stu stuart.hungerf...@gmail.com wrote: I'm trying to create a java.awt.Color class instance from within Clojure, using this constructor: Color(ColorSpace cspace, float[] components, float alpha) But always end up with a No matching ctor found for class java.awt.Color exception. I can create the ColorSpace instance as I expected, but I think I'm missing something with the rest of the Color constructor. I've tried changing the components to a vector of floats or a Java array of floats with no luck. -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: help--reading keyboard input from Clojure is surprisingly difficult
On Apr 9, 2011, at 6:18 PM, Sean Corfield wrote: On Sat, Apr 9, 2011 at 6:46 AM, Lee Spector lspec...@hampshire.edu wrote: But still, I will humbly submit that it's totally freakin' nutso that it should be so hard to do basic user interaction. I'm curious as to what percentage of developers are writing console-based applications (in any language)? I don't know -- probably quite low -- but I would predict that the percentage of students learning Lisp-like languages who would be writing console-based interactive programs is quite high. Lots of curricula are based on this sort of thing, and even people who aren't students may do some of this first since it seems like it shouldn't rely on understanding libraries or the java ecosystem or whatever. So funky behavior related to simple text I/O may be confusing people who are least likely to know how to work around it. What do the processes look like in other languages? How are those processes different to what happens with Clojure? Code for doing this sort of thing in Common Lisp or Scheme looks almost identical to the simple Clojure code we've seen on this thread, with the most significant difference being that the Clojure version apparently doesn't work if you launch your REPL and run your code in some of the commonly recommended ways. (Note: I haven't tried all of the ways that have been discussed, but the consensus seems to be that it does indeed fail.) -Lee -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: help--reading keyboard input from Clojure is surprisingly difficult
On Sat, 9 Apr 2011 19:27:13 -0400 Lee Spector lspec...@hampshire.edu wrote: On Apr 9, 2011, at 6:18 PM, Sean Corfield wrote: On Sat, Apr 9, 2011 at 6:46 AM, Lee Spector lspec...@hampshire.edu wrote: But still, I will humbly submit that it's totally freakin' nutso that it should be so hard to do basic user interaction. I'm curious as to what percentage of developers are writing console-based applications (in any language)? I don't know -- probably quite low -- but I would predict that the percentage of students learning Lisp-like languages who would be writing console-based interactive programs is quite high. I wouldn't expect it to be quite low, but I build them regularly, and so do most of the people I work with. On unix systems, the predominate way to plug to programs together is still via the standard IO pipes, which the programs - even if normally invoked from some visual tool - can be used from the command line. And many of us work develop on one system, then deploy on something else via SSH, so being able to deal with things on the command line - even if it also provides some kind of GUI - is a useful feature. Admittedly, JVM languages don't lend themselves to such things, what with having to either start it on every command or have some kind of server running to avoid that. Code for doing this sort of thing in Common Lisp or Scheme looks almost identical to the simple Clojure code we've seen on this thread, with the most significant difference being that the Clojure version apparently doesn't work if you launch your REPL and run your code in some of the commonly recommended ways. This sounds more like an issue with those commonly recommended ways than with clojure or it's REPL, since it works fine running from a shell. mike -- Mike Meyer m...@mired.org http://www.mired.org/consulting.html Independent Software developer/SCM 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: ANN: Logos v0.6 - Pattern matching, Tabling, Disequality Constraints, and now on Clojars
Fascinating! -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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: Announcement: pretzel - a predicate library + call for suggestions
On 9 April 2011 10:07, Ken Wesson kwess...@gmail.com wrote: That particular example ties a predicate to a particular error message. Error messages should be independent of predicates, otherwise they can't be localized or changed to fit a specific situation. It can always be an integer or a keyword (or a string!) used to look up the localized or situation-specific message in a map. It's still not as flexible, because different keywords with the same validation may require different error messages. It could perhaps work with a Turing-complete localization system, i.e. one where localizations are performed by arbitrary scripts, but I don't think a validation system should depend on having a sophisticated localization system. I also don't like the idea of tying together two pieces of functionality that could conceivably be separated. I prefer simple functions over compound ones. This would lead to a lot of validations with not in front of them. i.e not-email-address?, not-integer?, etc. So? It's redundant, doesn't read as well, and reverses people's usual conceptions about validations. I'd prefer treating validations as a contract, i.e. defining what user data must do to pass, rather than what it must do to fail. - James -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to access specific java.awt.Color constructor?
On Apr 10, 8:35 am, Alan a...@malloys.org wrote: You probably weren't putting it into a java float array, but instead a Float array (boxed type). Here's a repl session doing what you want. I don't know anything about colorspaces so it's probably nonsense, but it creates a Color with that constructor. Thanks Alan -- I realize now there's a subtle but important distinction there when doing Java interop. Stu -- You received this message because you are subscribed to the Google Groups Clojure group. To post to this group, send email to clojure@googlegroups.com Note that 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
