http://blog.gmane.org/gmane.comp.java.clojure.user hourly 1 1901-01-01T00:00+00:00 http://gmane.org/img/gmane-25t.png http://gmane.org http://comments.gmane.org/gmane.comp.java.clojure.user/72327 <pre>Hello, This is my first post to this group. If my post or the tone of my post is not up to this communities standards, please give me feedback so that I can integrate with the community. I'm coming from Scala-land. In Scala, there's a PartialFunction: http://www.scala-lang.org/archives/downloads/distrib/files/nightly/docs/library/index.html#scala.PartialFunction The key take-away for PartialFunctions is "... is a unary function where the domain does not necessarily include all values of type A." The ability to test a PartialFunction to see if the domain includes a particular value is very helpful. pf.isDefinedAt(x) allows testing to see if the function is defined at a given value of x. But a PartialFunction is a subclass of Function, so PartialFunctions can be applied: pf(x) The Scala compiler will take a pattern and turn it into a PartialFunction: def pf: PartialFunction[String, Number] = { case "" =&gt; 0 // special case blank to zero case x if isInt(x) =&gt; x.toInt case x if isDouble(x) =&gt; x.toD</pre> David Pollak 2013-05-25T16:14:01 http://comments.gmane.org/gmane.comp.java.clojure.user/72325 <pre>Wondering if anyone can give me some pointers with this, as I dive into logic programming. Or point me to a more appropriate forum, if this is the wrong one. I know a lot of you have been trying out core.logic. It was all going well until chapter four. The story so far: introduce some simple function, like cdr, then develop a logic programming equivalent, repeat. Then in chapter four we get the second commandment, and the equivalent functions stop being equivalent. Instead, they generate meaningless results, like 4.18, where the value of z is irrelevant to whether the equivalent function (mem) would succeed, since the target pattern appears earlier in the list, but memo outputs an infinite number of the target pattern. Or they generate incorrect results, like 4.31, where some of the patterns do not satisfy the equivalent function (rember), like (a b _.0 d e): z can't be removed unless it unifies with y, in which case y would have been removed, not z. The chapter concludes by highlighting this </pre> Brian Craft 2013-05-25T17:21:08 http://comments.gmane.org/gmane.comp.java.clojure.user/72324 <pre>I'm currently working on a book on concurrent/parallel development for The Pragmatic Programmers. One of the subjects I'm covering is parallel programming in Clojure, but I've hit a roadblock with one of the examples. I'm hoping that I can get some help to work through it here. The example counts the words contained within a Wikipedia dump. It should respond well to parallelisation (I have Java and Scala versions that perform excellently) but I've been incapable of coming up with a nice solution in Clojure. The code I'm working with is checked into GitHub: The basic sequential algorithm is: If I run that on the first 10k pages in Wikipedia dump, it takes ~21s on my MacBook Pro. One way to parallelise it is to create a parallel version of frequencies that uses reducers: And sure enough, if I use that, along with use the foldable-seq utility I posted about here are while ago it runs in ~8s, almost a 3x speedup, not bad given that the parallel version is unable to use transients. Unfortunately, as th</pre> Paul Butcher 2013-05-25T16:34:15 http://comments.gmane.org/gmane.comp.java.clojure.user/72323 <pre>I'm writing a generic database API, and would love some advice on how you think it should handle field types. Let me give a little background. My project's goal is to offer a single, simplified, Clojure-friendly API for most of your data persistence needs, so that: - you can easily use it in idiomatic Clojure since its API is composable - you can focus on your domain logic since the API is simple - you can easily use an in-memory backend in tests - several backends can be written, for Mongo, Postgres, GAE, etc You can see the intended usage in the readme&lt;https://github.com/evanescence/datamapper&gt;. (Note: it's not even close to working yet.) Now, I've already designed most of the public API&lt;http://evanescence.github.io/datamapper/datamapper.core.html&gt;and the backend interface&lt;http://evanescence.github.io/datamapper/datamapper.interface.html&gt;. But now I need to change both to accomodate field types. Problem is, I don't fully understand how types come into play. This is my rough understanding: First, when</pre> Steven Degutis 2013-05-25T16:00:26 http://comments.gmane.org/gmane.comp.java.clojure.user/72294 <pre>There are two patterns I find in my code that I'm still unhappy with but I don't know how to clean up. The first is: (if (:attr obj) obj (assoc obj :attr something)) I'm basically saying, give this hash-map an attribute if it doesn't already have it. And just return the thing with an attribute, regardless if I had to add it or not. This version is ugly because it repeats obj three times. I could write my own macro to de-duplicate it, but I avoid doing that when I can because there's usually a better built-in solution that I just don't know about yet. The second is like it: (if (some-test obj) obj (some-transformation obj)) In this one, I just want to return the object, but maybe transform it first. But the reference to obj happens three times! Still feels like it could be cleaned up. Any thoughts on how to clean these up? </pre> Steven Degutis 2013-05-25T11:24:29 http://comments.gmane.org/gmane.comp.java.clojure.user/72293 <pre>I am missing something obvious... I get a list of maps back from a function and I want to find the elements with nil (({:a2p-id "1", :dh-uuid "abc-def-ghi-klm"} {:a2p-id "2", :dh-uuid "def-ghi-klm-opq"} {:a2p-id "3", :dh-uuid nil}) ({:a2p-id "1", :dh-uuid "abc-def-ghi-klm"} {:a2p-id "2", :dh-uuid "def-ghi-klm-opq"} {:a2p-id "3", :dh-uuid nil})) I try the select function but it has no effect ... same list (set/select #(not (:dh-uuid %)) (map find-records query-parts)) also tried the previously working example... same list (filter #(not (:dh-uuid %)) (map find-records query-parts)) I am assuming that I am not indexing into each of the maps but I cannot remember or find out how to do this ... all examples only show one map Thanks Ray </pre> Mond Ray 2013-05-25T11:21:22 http://comments.gmane.org/gmane.comp.java.clojure.user/72285 <pre>Please note, this is a duplicate post of a stackoverflow question I just posted, Im extremely stumped and dont know what to make of this http://stackoverflow.com/questions/16747039/clojure-major-emergency-with-import This is really important, and I am totally stumped and on a deadline. Help is greatly appreciated. I have a Clojure project called red-black, which in particular contains a file called interval_tree.clj I have been compiling this project with lein uberjar and then using the resulting jar in other projects by installing it in a local maven repository. For example, in some project that uses the red-black project: mvn install:install-file \ -Dfile=../red-black/target/red-black-0.1.0.jar \ -DgroupId=self \ -DartifactId=red-black \ -Dversion=0.1.0 \ -Dpackaging=jar \ -DgeneratePom=true \ -DcreateChecksum=true \ -DlocalRepositoryPath=local_mvn_repo The crazy thing is, I added a new function, compiled my jar </pre> David Williams 2013-05-25T06:29:21 http://comments.gmane.org/gmane.comp.java.clojure.user/72284 <pre>This is really important, and I am totally stumped and on a deadline. Help is greatly appreciated. I have a Clojure project called red-black, which in particular contains a file called interval_tree.clj I have been compiling this project with lein uberjar and then using the resulting jar in other projects by installing it in a local maven repository. mvn install:install-file \ -Dfile=../red-black/target/red-black-0.1.0.jar \ -DgroupId=self \ -DartifactId=red-black \ -Dversion=0.1.0 \ -Dpackaging=jar \ -DgeneratePom=true \ -DcreateChecksum=true \ -DlocalRepositoryPath=local_mvn_repo The crazy thing is, I added a new function, compiled my jar and reinstalled it in the local maven repository of another project, and now java cant find my new function user=&gt; (red-black.interval-tree/tree-to-flat-list ) CompilerException java.lang.RuntimeException: No such var: red-black.interval-tree/tree-to-flat-list, compiling</pre> David Williams 2013-05-25T07:00:15 http://comments.gmane.org/gmane.comp.java.clojure.user/72278 <pre>I saw mention of Wisp the other day (on Hacker News, IIRC), but I haven't noticed any discussion of it on the Clojure email list, (def newsletter), etc: Wisp is a homoiconic JavaScript dialect with clojure syntax, s-expressions and macros. Unlike clojurescript, Wisp code compiles to human-readable JavaScript. The goal of Wisp is to compile to the JavaScript you would have written anyway. Think of Wisp asmarkdown for JS programing! Homoiconic syntax and macros are the primary motivations! -- https://github.com/Gozala/wisp See also http://jeditoolkit.com/try-wisp/ Has anyone here played with Wisp? Any reactions? -r -- http://www.cfcl.com/rdm Rich Morin http://www.cfcl.com/rdm/resume rdm&lt; at &gt;cfcl.com http://www.cfcl.com/rdm/weblog +1 650-873-7841 Software system design, development, and documentation </pre> Rich Morin 2013-05-24T23:59:22 http://comments.gmane.org/gmane.comp.java.clojure.user/72275 <pre>Hey Folks, We've just released the 0.1.7 versions of the Pedestal libraries. The big feature in this release is a much simplified dataflow engine for the client-side. We're still behind on documentation and samples, but with this change our focus finally shifts directly to improving those two things. Expect more details in the coming weeks and months. I hope to write a blog article in the next week or so showcasing what the new dataflow engine can do. You'll find the full changelog for this and other changes here: http://git.io/dHCnJQ. - Ryan and the rest of the Pedestal team </pre> Ryan Neufeld 2013-05-24T20:38:21 http://comments.gmane.org/gmane.comp.java.clojure.user/72270 <pre>Hi everyone, I am trying to do something very simple like asking the user whether he wants to continue or not (a-la bash). However, sometimes the print statement is printed sometimes it isn't! IN other words sometimes I get the prompt ,sometimes it looks like it's hanging (while in fact it's waiting for the user to type \y or ) and it's printing the warning altogether with what the user typed and the rest of the output...weird stuff! (print " \u001B[31mYOU ARE PERFORMING A POTENTIALLY ILLEGAL OPERATION...\n\t PROCEED AT YOUR OWN RISK!!!\u001B[m Proceed? (y/n):") (when (-&gt; *in* (java.util.Scanner.) .next (.charAt 0) (= \y)) any ideas? Jim </pre> Jim - FooBar(); 2013-05-24T19:35:07 http://comments.gmane.org/gmane.comp.java.clojure.user/72265 <pre>Hello Clojurians, I'm sure that everyone here is pretty well sold on the idea that Git is nearly always a better SCM choice than Perforce, etc. I recently had to do a comparison at work highlighting the differences between the two systems as we try to move from a legacy home-grown SCM solution to a more modern approach. The result is posted at the link below in case you find it useful in making a similar argument. Enjoy! http://cooljure.blogspot.com/2013/05/hello-all-this-is-my-very-first-post-on.html Alan Thompson </pre> Alan Thompson 2013-05-24T18:19:03 http://comments.gmane.org/gmane.comp.java.clojure.user/72261 <pre>Hi, I would like to announce two wrappers that we developed for ClojureScript testing. They provide support for Mocha&lt;http://visionmedia.github.io/mocha/&gt; and Chai &lt;http://chaijs.com/&gt; respectively. The wrappers play well with testing setups on node and in the browser (or in headless setups via mocha-server&lt;https://github.com/carbonfive/mocha-server&gt; ). https://github.com/contentjon/mocha-latte https://github.com/contentjon/chai-latte Enjoy, Jan </pre> jkrueger 2013-05-24T16:58:58 http://comments.gmane.org/gmane.comp.java.clojure.user/72258 <pre>I am starting out to use Clojure to combine and verify data between DB2 on a Mainframe, SQL Server and an Atom Feed. Yes, it's such fun working in a start-up ;-) Database wise, all is connecting OK after some Leiningen shenanigans and I am now stuck on the mapping part ;-) The code is below. I want to generate a set of maps that show the following: #({:a2pid 269, :uuid nil} {:a2pid 270, :uuid nil} {:a2pid 258, :uuid nil} {:a2pid 261, :uuid nil} {:a2pid 251, :uuid E7D4262C-62B3-4129-9CE4-B342DC1C39FC}) The idea is to have a list of maps that can show where there are gaps between the two DBs and, coming next, the Atom feed. It is essentially a join operation - and maybe that's what I need but I cannot figure out where to plonk the magic words. (defn a2p-records-by-date [query from-date to-date dh-sub-query] (sql/with-connection db2 (sql/with-query-results rs [query from-date to-date] (doseq [row rs] (println (str " " (:project_id row) (dh-sub-query (:project_id row)))))))) (defn </pre> Mond Ray 2013-05-24T14:55:17 http://comments.gmane.org/gmane.comp.java.clojure.user/72257 <pre>Hi, I just released liberator 0.9.0. You'll find the new documentation and tutorial site at http://clojure-liberator.github.io/liberator/ Have fun! And thanks to all contributors, -billy. </pre> Philipp Meier 2013-05-24T14:08:10 http://comments.gmane.org/gmane.comp.java.clojure.user/72250 <pre>I'm thinking of making a game in Clojure for this competition: http://lispinsummerprojects.org/. However, I'm not sure if the best way to go is HTML5 with ClojureScript or a Java applet.... More specifically, I'd like to do HTML5, but am unsure of the current capabilities of ClojureScript. Any advice would be appreciated. </pre> JvJ 2013-05-24T09:22:20 http://comments.gmane.org/gmane.comp.java.clojure.user/72238 <pre> Hello, can anyone give a hint on real-world Clojure application? I would like to compare applications written in different dynamic JVM languages with respect to different JVM characteristics. Usually this kind of things are done by means of benchmarking, however, no benchmarking suite exists for scripting languages. Available ones are for Java and Scala. There is also a Programming Languages Shootout Project (http://benchmarksgame.alioth.debian.org/), but the applications there are relatively small and CPU-intensive. Ideally, I would like to have a real-world applications (but not interactive ones, since it's not trivial to make it deterministic and will require automatization of the user behavior) that consume some input and produce some output. In this way I can profile the underlying JVM and collect metrics of interest. I've tried to search on GitHub, but failed. If you read a research paper comparing different JVM languages, what kind of applications you expect to be compared? I'm lookin</pre> bekon 2013-05-23T09:25:44 http://comments.gmane.org/gmane.comp.java.clojure.user/72223 <pre>Is "the ground truth" your spec or your code? Here is an interesting read: http://shanecelis.github.io/2013/05/20/why-im-trying-literate-programming Shane started with a co-worker, working from a spec, to create a program. He eventually found that only he could make changes because only he understood the code and the spec was out of date. The last big project I worked on had 6 people for 6 years. The central data structure eventually became complex. It had optimizations and mountains of code that depended on them. When we tried to write a new and "better" central algorithm it turned out that nobody knew all the various substructures embedded in the main data structure so we couldn't make the improvement. The person who "managed" the main data structure had left the project, taking with him all the knowledge. The program died. Are you limiting our ability to collaborate because you don't communicate? Do we have to read (and reverse engineer) your code before we can write? Does your code "add, change, or</pre> Tim Daly 2013-05-22T17:29:59 http://comments.gmane.org/gmane.comp.java.clojure.user/72198 <pre>I'm studying for an interview and thought it might be nice to know the time complexity of primitive operations on collections in Clojure. A quick googling didn't turn up a definitive resource. I would be happy to put one together. What I had in mind was something like: Collections: strings, sets, maps, Java arrays, lists, vectors Operations: peek, pop, conj, cons, assoc/dissoc, get, nth, count What I have in mind is to fill out this table with the appropriate average big-O (my *guesses* from googling/experimenting/thinking are entered, and may be completely wrong!; sorry for any formatting problems due to varying type styles, perhaps I should have used s-expressions :-) - should be OK with fixed width font): Collection get nth cons conj assoc pop peek count List "1"? "1"? 1 1 X 1 1 1 Vector "1" "1"? n 1 "1"? 1 1 1 Set "1" X "1" "1" X X X 1? Map "1" X 1 "1"? "1"? X</pre> John Jacobsen 2013-05-22T14:05:45 http://comments.gmane.org/gmane.comp.java.clojure.user/72188 <pre> I'm pleased to announce the release of tawny-owl 0.11. What is it? ========== This package allows users to construct OWL ontologies in a fully programmatic environment, namely Clojure. This means the user can take advantage of programmatic language to automate and abstract the ontology over the development process; also, rather than requiring the creation of ontology specific development environments, a normal programming IDE can be used; finally, a human readable text format means that we can integrate with the standard tooling for versioning and distributed development. Changes ======= # 0.11 ## New features - facts on individual are now supported - documentation has been greatly extended - OWL API 3.4.4 A new paper on the motivation and use cases for tawny-owl is also available at http://www.russet.org.uk/blog/2366 https://github.com/phillord/tawny-owl Feedback welcome! </pre> Phillip Lord 2013-05-22T11:41:33 http://comments.gmane.org/gmane.comp.java.clojure.user/72179 <pre> Hi, We have built a web application using grails framework and we use Groovy, Java and Clojure programming languages. We use Clojure 1.2. The clojure files include classes from HTMLUnit. Recently HTMLUnit released a new version of JAR file and we were trying to migrate the web app to new version of HTMLUnit. When we deploy the web app under Jetty (comes with Grails), during the deployment the Clojure code which uses HTMLUnit fails with ClassNotFound Exception. What is the reason for this error and any help or pointers to solve this issue is greatly appreciated. Looking forward to your reply. Regards Vasu </pre> vcomandur< at >gmail.com 2013-05-22T06:25:55 Search the mailing list at Gmane query http://search.gmane.org/?group=$group=gmane.comp.java.clojure.user