Re: unchecked methods for floats/doubles?
Excellent - thanks for clarifying this! - Korny On Sun, Feb 8, 2009 at 12:27 AM, Rich Hickey richhic...@gmail.com wrote: On Feb 7, 2009, at 3:43 AM, Korny Sietsma wrote: Ah - I didn't realise that. I was trying to avoid the overhead, as I understood it, of both converting the parameters to Float/Double objects, and then of checking for overflow. So '*' and '+' don't do overflow checking - do they need to convert primitives to/from objects? Specifically, when I call: (loop [x (double x) y (double y)] ... do maths to x and y (recur x y) ) Is it going to have to convert x and y between 'double' and 'Double' at all, or will it just work with primitive types??? This will declare the locals x and y to be primitive doubles, converting once on entry, and all math ops involving them and other primitives will be primitive. Also, if you accidentally try to recur with a boxed value you will get an error. Rich -- Kornelis Sietsma korny at my surname dot com kornys on gmail, twitter, facebook, etc. Every jumbled pile of person has a thinking part that wonders what the part that isn't thinking isn't thinking of --~--~-~--~~~---~--~~ 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 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: Newbie: applying arguments into a macro
Hi, Am 08.02.2009 um 00:40 schrieb samppi: (defn conc* [tokens subrules] (loop [subrule-queue (seq subrules), remaining-tokens (seq tokens), products []] (if (nil? subrule-queue) [products remaining-tokens] (let [[subrule-products subrule-remainder :as subrule-result] ((first subrule-queue) remaining-tokens)] (when-not (nil? subrule-result) (recur (rest subrule-queue) subrule-remainder (conj products subrule-products))) (defmacro conc [ subrules] `(fn [tokens#] (conc* tokens# ~...@subrules))) I had another function called factor=: (defn factor= [factor subrule] (apply conc (replicate factor arg))) When I changed conc to a macro, factor= didn't work anymore. Is there no way of fixing factor=? Why don't you call conc* directly? (defn factor= [factor subrule] (fn [tokens] (apply conc* tokens (replicate factor subrule That's another nice example why to pack as much as possible into a function, which is then called by the expanded macro code. Sincerely Meikel smime.p7s Description: S/MIME cryptographic signature
Re: ANN: clojure.contrib.error-kit
So far this is fantastic! And I haven't even got around to playing with the
restart mechanism :) I'm using it in Spinoza to provide contextual errors
(malformed slot list, missing base class etc.). I notice the contrib
libraries in general are very good at throwing exceptions so that consumers
have some idea of what is going on. error-kit one ups this practice by
providing a standardized way to define your errors up front and presents a
definition system that removes the need to instantiate ugly Java Exceptions
inline with your code.
(defn protocol-fn [protocol-name fn-name]
(let [protocol-keyword (symbol-to-keyword protocol-name)
dispatch (partial protocol-dispatch protocol-keyword)]
`(do
(defmulti ~fn-name ~dispatch)
(defmethod ~fn-name [:spinoza/object nil]
[~'obj]
(raise *missing-protocol-method-error*
~'obj ~(str protocol-name) ~(str fn-name))
Where the error is defined as you've described:
(deferror *missing-protocol-method-error* [*spinoza-error*]
[obj protocol-name method-name]
{:msg (str (:tag obj)
class does not implement
method-name
from protocol
protocol-name)})
Sweet!
That said I do have one minor annoyance and that is the need to leave an
empty bracket if you want to create a new error without inheriting from a
previously defined error. Very minor. Will provide feedback on restarts
when I get there.
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Re: ANN: clojure.contrib.error-kit
On Sun, Feb 8, 2009 at 5:18 AM, David Nolen dnolen.li...@gmail.com wrote: Sweet! I'm glad it's working for you, and that you have figured out how to use it despite the almost complete lack of docs. :-P That said I do have one minor annoyance and that is the need to leave an empty bracket if you want to create a new error without inheriting from a previously defined error. Very minor. This was actually intentional. I had a pre-release version where those brackets were optional, but the doc-string could still be specified. But I was worried this would be too confusing since it meant that if you then inserted the parent vector, that would have to come before the doc-string, but the args vector would have to be inserted after. (deferror *foo* Foo Error) (deferror *foo* [*bar*] Foo Error) (deferror *foo* Foo Error [arg1]) (deferror *foo* [*bar*] Foo Error [arg1]) And perhaps worst, if you got it wrong, I may not be able to detect the mistake: (deferror *foo* Foo Error) (deferror *foo* Foo Error [*bar*]) (deferror *foo* Foo Error [*bar*] [arg1]) ; oops That last line would be using [*bar*] as the arg vector and [arg1] as the error object definition. ...anyway, that's reasoning behind requiring at least placeholder empty brackets before the doc-string. But I'm open to being persuaded otherwise. Perhaps allow no parent vector if there's also no doc-string? Oh, and by the way with an empty or missing parent vector, the error would still be derived from kit/*error*. Will provide feedback on restarts when I get there. Great! But they're called continues. :-) Seriously, if you think restart is a better name I'm willing to consider changing it. But Clojure already has retries in transactions, where code is actually re-run from the beginning. A restart doesn't re-run anything, it just skips forward over a certain number of returns and runs an alternate branch of code. continue seemed a better description of that to me than restart. --Chouser --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
if-let
Can someone show me an example of a good use of if-let? I find its doc string a little confusing. It says If test is true, evaluates then with binding-form bound to the value of test, if not, yields else. However, it doesn't have a parameter named test. I assume it means If the binding evaluates to true Also, it has a parameter named bindings, but it should perhaps be named binding because it doesn't allow specifying more than one binding. -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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: if-let
Hi, Am 08.02.2009 um 15:47 schrieb Adrian Cuthbertson: Here's one, I'm setting basedir to either :basedir in a map in *locs (a thread-local var) or to . if :basedir was not found in the map... (let [basedir (if-let [bdir (:basedir *locs)] bdir .)] ...) i.e bdir assumes the value of the test and if that is not false (or nil) returns it otherwise the else part. This can be written more concise with get or even with :basedir alone: (let [basedir (get *locs :basedir .)] ...) (let [basedir (:basedir *locs .)] ...) (let [basedir (*locs :basedir .)] ...) All but the last form work also if *locs is nil. Sincerely Meikel smime.p7s Description: S/MIME cryptographic signature
Re: if-let
Thanks Meikel. There's always something new to learn. I'm also fast learning that if something doesn't look quite elegant in one's code, then there's bound to be an elegant clojure way of doing it! On Sun, Feb 8, 2009 at 4:51 PM, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 08.02.2009 um 15:47 schrieb Adrian Cuthbertson: Here's one, I'm setting basedir to either :basedir in a map in *locs (a thread-local var) or to . if :basedir was not found in the map... (let [basedir (if-let [bdir (:basedir *locs)] bdir .)] ...) i.e bdir assumes the value of the test and if that is not false (or nil) returns it otherwise the else part. This can be written more concise with get or even with :basedir alone: (let [basedir (get *locs :basedir .)] ...) (let [basedir (:basedir *locs .)] ...) (let [basedir (*locs :basedir .)] ...) All but the last form work also if *locs is nil. 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 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 -~--~~~~--~~--~--~---
Pmapping force over treed delays
Hi all, Say I have a collection of delays, some of which need to get others' values in order to compute (there are no cyclic dependencies). If I just pmap force over the entire collection, do I run the risk of filling up a thread pool with operations that aren't ready to go yet? Would it be better to represent the collection as a tree-seq and then pmap force over that? Many thanks, Anand --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Discarding entire transactions
Hello again, In my application, I'll frequently want to quickly discard all the changes made during a transaction involving many refs. I don't want to force the refs to roll back to their values at the beginning of the transaction, I just want to end the transaction immediately and skip the write stage; updates made in other transactions should still 'stick'. What's the most efficient way to do this? Thanks again! Anand --~--~-~--~~~---~--~~ 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 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: Questions about a Clojure Datalog
reposted to correct a mistake in my use of X, Y and Z: --- I agree with Jeffrey that there is no reason to have just one option. Sometimes you want your reasoner to find a single model; sometimes you want it to find all models (assuming you are reasoning over a finite set). I've appended a long rant about SAT-based reasoners and open-world semantics. I hope it is relevant, and apologize for the length. -John Initially, I had a lot of trouble understanding why the concept of satisfiability was relevant to reasoning. I just wanted to know whether or not a sentence was true; whether or not it was satisfiable didn't seem relevant. Here's how you *could* use a SAT solver to answer a practical question (later I will explain why you would want to): Let's say you have a list of sentences A: A = ((man socrates) (for all X: man X - mortal X)). A is your database of previous assertions. Now let's say that you want to determine the truth state of a new sentence B: B = (mortal socrates) In other words, you want to know whether or not B is true, given all your previous assertions A. So you form two new sentences, Y Z: Y = (A and B) = ((man socrates) and (for all X: man X - mortal X) and (mortal socrates)) Z = (A and (not B)) = ((man socrates) and (for all X: man X - mortal X) and (not (mortal socrates))) You then plug Y into your SAT solver, and also plug Z into your SAT solver. If Y is satisfiable and Z is satisfiable, then we say that B's truthstate, relative to A, is UNKNOWN. If Y is satisfiable and Z is unsatisfiable, then we say that B's truthstate, relative to A, is TRUE. If Y is unsatisifiable and Z is satisfiable, then we say that B's truthstate, relative to A, is FALSE. If Y is unsatisfiable and Z is unsatisfiable, then we say that B's truthstate, relative to A, is CONTRADICTION. In this example, I'm pretending we have a first-order logic SAT solver (i.e. we can quantify, and our predicates take arguments), whereas usually we only have a boolean logic SAT solver, but the former can be easily built upon the latter (although it would be more efficient to build a first-order SAT solver). Also, the actual implementation can be much more optimized than this; there is usually overlapping work done during the evaluation of X and Y. This example only shows you how to evaluate (truthstate A B). If you wanted to find a *model* (i.e. a list of tuples of things that satisfy some sentence), then you would say something like get X: red X (i.e. get me all X's that you can prove are red). In a system with finitely many things, the vanilla unoptimized reasoner simply loops through each thing in the system and asks for its truthstate: for each X: if (truthstate A (red X)) == TRUE: add X to output There can be situations where you would want, not just the things for which the predicate is TRUE, but also the things for which the predicate is UNKNOWN. You can include that as a argument to your query. Also, there is a separate mechanism for performing default reasoning (which I am eliding here because this is already a pretty long rant). Why go through all this trouble to get open-world semantics? Why not just use a close-world reasoner? First, I think open-world semantics does a better job of mimicing human reasoning. If humans don't know that a sentence is true, they don't generally conclude that it's false. Second, basing your reasoner on a SAT solver makes a lot of sense computationally. SAT is a hard problem (NP-complete), but so much work has been done on it that in practice we can solve very large instances efficiently (and any SAT problem is solvable given enough time and memory). The underlying SAT solvers seem to be improving at a tremendous rate, so a system that interfaces to them benefits from all that work. -John On Sat, Feb 7, 2009 at 11:25 AM, John Fries john.a.fr...@gmail.com wrote: I agree with Jeffrey that there is no reason to have just one option. Sometimes you want your reasoner to find a single model; sometimes you want it to find all models (assuming you are reasoning over a finite set). I've appended a long rant about SAT-based reasoners and open-world semantics. I hope it is relevant, and apologize for the length. -John Initially, I had a lot of trouble understanding why the concept of satisfiability was relevant to reasoning. I just wanted to know whether or not a sentence was true; whether or not it was satisfiable didn't seem relevant. Here's how you *could* use a SAT solver to answer a practical question (later I will explain why you would want to): Let's say you have a list of sentences A: A = ((man socrates) (for all X: man X - mortal X)). A is your database of previous assertions. Now let's say that you want to determine the truth state of a new sentence B: B = (mortal socrates) In other words, you want to know whether or not B is true, given all your previous assertions A. So you form two new sentences, Y Z: X = (A and B)
Re: IntelliJ Plugin -- Wonderful News!
I am using IDEA 9164. Make sure idea.jar is on your classpath (it is not part of the Development SDK). BTW to original plugin is still available pre-built. It works fine on Linux and Windows. See http://code.google.com/p/clojure-intellij-plugin/ Howard Lewis Ship wrote: I'm trying to build this locally; I haven't built an IDEA plugin before. Anyway, I've downloaded the 8.0.1 dev kit and installed it, but class com.intellij.openapi.module.JavaModuleType doesn't exist, although this a JAR with other classes from that package. I must have the wrong version of the dev kit; what's the correct version to be using? Thanks, Howard On Fri, Feb 6, 2009 at 7:53 AM, Tom Ayerst tom.aye...@gmail.com wrote: That is excellent news. Now I just to learn enough Clojure to properly contribute to a pukka open Source project so I can get a free copy ;-) 2009/2/6 Peter Wolf opus...@gmail.com Check out this email! IntelliJ is going to get a *really* good plugin for Clojure :-D I have gladly turned control of the my plugin over to Ilya, and the code has been moved to the JetBrains SVN. I will remain involved and fix bugs as they are found, but Ilya and his team are adding a real test suite, Mac support, and implementing things like the debugger that are not currently documented. I notice that Ilya has already added lots of new stuff, I am trying it now. There is not an release yet, but here is the new code location if you want to build it yourself. http://svn.jetbrains.org/idea/Trunk/clojure-plugin Enjoy (Greatly) Peter Hello, Peter. I'm going to develop plugin for IntelliJ IDEA for Clojure language. Talking with Rich I knew about your plugin, which already has parser and several nice features, based on it withou Program Structure Interface. To not duplicate code I would like to suggest you to move your source into JetBrains source repository and continue working on plugin together. Of course, Clojure plugin will stay open-source project. Moreover we already have off-the shelf process to build such projects and perform continuous integartion using our buildserver TeamCity. As you might know, I was developing Groovy plugin (wich you took as a base for your) for two years and now I lead development of Scala plugin. Main feature of all of them is full interoperability with main Java support, so I would like to keep it for Clojure too. So, what do you think about this cooperation? If you agree I'll submit existing code to our repository and provide commit rights for you. With best regards, Ilya --~--~-~--~~~---~--~~ 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 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: Newbie: applying arguments into a macro
Oh, yeah. Silly me, I *can* do that. Thanks a lot. It works like a charm now. On Feb 8, 2:17 am, Meikel Brandmeyer m...@kotka.de wrote: Hi, Am 08.02.2009 um 00:40 schrieb samppi: (defn conc* [tokens subrules] (loop [subrule-queue (seq subrules), remaining-tokens (seq tokens), products []] (if (nil? subrule-queue) [products remaining-tokens] (let [[subrule-products subrule-remainder :as subrule-result] ((first subrule-queue) remaining-tokens)] (when-not (nil? subrule-result) (recur (rest subrule-queue) subrule-remainder (conj products subrule-products))) (defmacro conc [ subrules] `(fn [tokens#] (conc* tokens# ~...@subrules))) I had another function called factor=: (defn factor= [factor subrule] (apply conc (replicate factor arg))) When I changed conc to a macro, factor= didn't work anymore. Is there no way of fixing factor=? Why don't you call conc* directly? (defn factor= [factor subrule] (fn [tokens] (apply conc* tokens (replicate factor subrule That's another nice example why to pack as much as possible into a function, which is then called by the expanded macro code. Sincerely Meikel smime.p7s 5KViewDownload --~--~-~--~~~---~--~~ 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 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: Discarding entire transactions
I don't think you can. There is no rollback function available. On Sun, Feb 8, 2009 at 12:23 PM, Anand Patil anand.prabhakar.pa...@gmail.com wrote: Hello again, In my application, I'll frequently want to quickly discard all the changes made during a transaction involving many refs. I don't want to force the refs to roll back to their values at the beginning of the transaction, I just want to end the transaction immediately and skip the write stage; updates made in other transactions should still 'stick'. What's the most efficient way to do this? Thanks again! Anand --~--~-~--~~~---~--~~ 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 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: Discarding entire transactions
On Feb 8, 7:29 pm, Shawn Hoover shawn.hoo...@gmail.com wrote: On Sun, Feb 8, 2009 at 12:23 PM, Anand Patil anand.prabhakar.pa...@gmail.com wrote: Hello again, In my application, I'll frequently want to quickly discard all the changes made during a transaction involving many refs. I don't want to force the refs to roll back to their values at the beginning of the transaction, I just want to end the transaction immediately and skip the write stage; updates made in other transactions should still 'stick'. What's the most efficient way to do this? Thanks again! Anand You can abort a transaction by throwing an exception, but in that case all refs automatically retain their pre-transaction values. You can't partially roll back a transaction, because by definition all changes to refs in a transaction occur or none do. By the way, what do you mean by other transactions? - Transactions running on other threads? Aborting in one thread does not affect refs in other threads. - Transactions that completed earlier in time on the same thread? Those values are not affected by aborting a later transaction. - dosync calling dosync on the same on the same thread? Aborting from an inner dosync aborts the whole stack of dosyncs in that thread. I think your first response covers my case. Here's an example of what I mean: (def a (ref 1)) (def b (ref 1)) ; Do these concurrently, either from separate agents or using pmap (dosync (commute b error-throwing-fn a)) (dosync (commute a + @b)) I want to have the option to abort the first transaction without rolling back the second. Based on what you said, if the first transaction is aborted but the second is not then no matter what a's value will be 2 and b's value will be 1, correct? Thanks for the replies, Anand --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
clojure.contrib.sql connections
I'm trying to use the sql contrib library to connect to a Postgres
database. It's not clear to me how to specify a username and password.
Here's what I'm trying.
(use 'clojure.contrib.sql)
(let [db-host localhost
db-name ct
db-port 5432
subname (str // db-host : db-port / db-name)]
(println subname = subname)
(def db {:classname org.postgresql.Driver ; must be in classpath
:subprotocol postgresql
:subname subname
:username mvolkmann
:password })
(with-connection db
(with-query-results rs [select * from ElementType]
(println rs
The error I get is org.postgresql.util.PSQLException: FATAL: no
PostgreSQL user name specified in startup packet. I think the problem
is that the username and password values in db aren't used by
with-connection unless a DataSource object is specified. However, it
doesn't seem like I should have to create one of those just to connect
to a relational database. Any idea what I'm doing wrong?
--
R. Mark Volkmann
Object Computing, Inc.
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ClassFormatError on compile
I am intermittently getting the following error when I attempt to perform an incremental compilation of a set of Clojure source files. To be clear, I mean incremental where I've previously compiled the sources down to classfiles, then changed one or more source files, and then run clojure.lang.Compile over all of the libs in the project, which should only compile the changed source files if I understand correctly. Cleaning the project (which deletes the classfiles from the old compilation run) and doing a full recompile of all libs works succeeds. - Chas Exception in thread main java.lang.ClassFormatError: Invalid method Code length 105496 in class file com/foo/MyClass__init at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClass(ClassLoader.java:675) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124) at java.net.URLClassLoader.defineClass(URLClassLoader.java:260) at java.net.URLClassLoader.access$000(URLClassLoader.java:56) at java.net.URLClassLoader$1.run(URLClassLoader.java:195) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:188) at java.lang.ClassLoader.loadClass(ClassLoader.java:316) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java: 288) at java.lang.ClassLoader.loadClass(ClassLoader.java:251) at java.lang.ClassLoader.loadClassInternal(ClassLoader.java: 374) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:247) at clojure.lang.RT.loadClassForName(RT.java:1512) at clojure.lang.RT.load(RT.java:394) at clojure.lang.RT.load(RT.java:374) at clojure.core$load__4911$fn__4913.invoke(core.clj:3623) at clojure.core$load__4911.doInvoke(core.clj:3622) at clojure.lang.RestFn.invoke(RestFn.java:413) at clojure.core$load_one__4863.invoke(core.clj:3467) at clojure.core$compile__4918$fn__4920.invoke(core.clj:3633) at clojure.core$compile__4918.invoke(core.clj:3632) at clojure.lang.Var.invoke(Var.java:336) at clojure.lang.Compile.main(Compile.java:56) --~--~-~--~~~---~--~~ 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 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.contrib.sql connections
On Feb 8, 2009, at 4:04 PM, Mark Volkmann wrote: The error I get is org.postgresql.util.PSQLException: FATAL: no PostgreSQL user name specified in startup packet. I think the problem is that the username and password values in db aren't used by with-connection unless a DataSource object is specified. That is not correct. When using the DriverManager parameter set, any other keys and values present in db will be passed along to the driver as properties. Based on this: http://jdbc.postgresql.org/documentation/81/connect.html it looks like PostgreSQL expects the key for the property identifying the user to be user, not username. --Steve smime.p7s Description: S/MIME cryptographic signature
Re: clojure.contrib.sql connections
Please let us know if this works. On Sun, Feb 8, 2009 at 4:23 PM, Stephen C. Gilardi squee...@mac.com wrote: On Feb 8, 2009, at 4:04 PM, Mark Volkmann wrote: The error I get is org.postgresql.util.PSQLException: FATAL: no PostgreSQL user name specified in startup packet. I think the problem is that the username and password values in db aren't used by with-connection unless a DataSource object is specified. That is not correct. When using the DriverManager parameter set, any other keys and values present in db will be passed along to the driver as properties. Based on this: http://jdbc.postgresql.org/documentation/81/connect.html it looks like PostgreSQL expects the key for the property identifying the user to be user, not username. --Steve --~--~-~--~~~---~--~~ 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 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.contrib.sql connections
On Sun, Feb 8, 2009 at 3:23 PM, Stephen C. Gilardi squee...@mac.com wrote: On Feb 8, 2009, at 4:04 PM, Mark Volkmann wrote: The error I get is org.postgresql.util.PSQLException: FATAL: no PostgreSQL user name specified in startup packet. I think the problem is that the username and password values in db aren't used by with-connection unless a DataSource object is specified. That is not correct. When using the DriverManager parameter set, any other keys and values present in db will be passed along to the driver as properties. Based on this: http://jdbc.postgresql.org/documentation/81/connect.html it looks like PostgreSQL expects the key for the property identifying the user to be user, not username. That worked! Thanks Steve and Jeffrey! -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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.contrib.sql connections
Great! On Sun, Feb 8, 2009 at 5:05 PM, Mark Volkmann r.mark.volkm...@gmail.comwrote: On Sun, Feb 8, 2009 at 3:23 PM, Stephen C. Gilardi squee...@mac.com wrote: On Feb 8, 2009, at 4:04 PM, Mark Volkmann wrote: The error I get is org.postgresql.util.PSQLException: FATAL: no PostgreSQL user name specified in startup packet. I think the problem is that the username and password values in db aren't used by with-connection unless a DataSource object is specified. That is not correct. When using the DriverManager parameter set, any other keys and values present in db will be passed along to the driver as properties. Based on this: http://jdbc.postgresql.org/documentation/81/connect.html it looks like PostgreSQL expects the key for the property identifying the user to be user, not username. That worked! Thanks Steve and Jeffrey! -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Am I holding on to the head here ?
I have this piece of code: (defn- run-work-elements-in-parallel Runs a group of work elements in parallel. Returns an extended database. [elements database] (assert (set elements)) (let [[rec simp] (separate :recursive elements) results-simp (pmap #(run-simple-work-element % database) simp) results-rec (map #(run-recursive-work-element % database) rec) results (concat results-simp results-rec)] (preduce union (cons database results The exact details aren't important. The let bindings results-simp, results-rec, and results are each a lazy stream. They can get quite large. Assuming preduce can iterate over them, is binding them in the let statement stopping them from getting garbage collected? If so, is the best solution to wrap them in a (fn [] ...) and then use them like (results)? 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 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: Am I holding on to the head here ?
I am not sure exactly how preduce differs from normal reduce, but reduce is not a lazy operation, so it will result in the realization of a lazy seq passed to it. On Sun, Feb 8, 2009 at 2:13 PM, Jeffrey Straszheim straszheimjeff...@gmail.com wrote: I have this piece of code: (defn- run-work-elements-in-parallel Runs a group of work elements in parallel. Returns an extended database. [elements database] (assert (set elements)) (let [[rec simp] (separate :recursive elements) results-simp (pmap #(run-simple-work-element % database) simp) results-rec (map #(run-recursive-work-element % database) rec) results (concat results-simp results-rec)] (preduce union (cons database results The exact details aren't important. The let bindings results-simp, results-rec, and results are each a lazy stream. They can get quite large. Assuming preduce can iterate over them, is binding them in the let statement stopping them from getting garbage collected? If so, is the best solution to wrap them in a (fn [] ...) and then use them like (results)? Thanks -- And what is good, Phaedrus, And what is not good— Need we ask anyone to tell us these things? --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
contrib sql - with-query-results macro
The second argument to the with-query-results macro needs to be a vector containing a query string and optional values to be inserted into the query if it is parameterized. Would it be difficult to change this so in the case that the query is not parameterized, a string can be passed for the second argument instead of a vector containing a single string? -- R. Mark Volkmann Object Computing, Inc. --~--~-~--~~~---~--~~ 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 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: Am I holding on to the head here ?
You're probably correct, but I'm still interested in the question in the more general sense. On Sun, Feb 8, 2009 at 5:17 PM, Kevin Downey redc...@gmail.com wrote: I am not sure exactly how preduce differs from normal reduce, but reduce is not a lazy operation, so it will result in the realization of a lazy seq passed to it. On Sun, Feb 8, 2009 at 2:13 PM, Jeffrey Straszheim straszheimjeff...@gmail.com wrote: I have this piece of code: (defn- run-work-elements-in-parallel Runs a group of work elements in parallel. Returns an extended database. [elements database] (assert (set elements)) (let [[rec simp] (separate :recursive elements) results-simp (pmap #(run-simple-work-element % database) simp) results-rec (map #(run-recursive-work-element % database) rec) results (concat results-simp results-rec)] (preduce union (cons database results The exact details aren't important. The let bindings results-simp, results-rec, and results are each a lazy stream. They can get quite large. Assuming preduce can iterate over them, is binding them in the let statement stopping them from getting garbage collected? If so, is the best solution to wrap them in a (fn [] ...) and then use them like (results)? Thanks -- And what is good, Phaedrus, And what is not good— Need we ask anyone to tell us these things? --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
clojure.inspector doesn't work on sets?
Hi all, I was using clojure.inspector in my code, and to my surprise it failed when I applied it to a structure containing sets. The error message was that nth is not supported on the type PersistentHashSet. I've included a trivial patch below that seems to fix the problem. I'm not sure I understand why this is happening though. The API docs note that nth works on seqs in O(n) time, and I thought that a set is- a seq? Explicitly coercing it to a seq seems to work, but what exactly is going on here? Is a new object being created, or are there any other efficiency concerns? Tim Index: src/clj/clojure/inspector.clj === --- src/clj/clojure/inspector.clj (revision 1252) +++ src/clj/clojure/inspector.clj (working copy) @@ -31,7 +31,9 @@ (defmethod is-leaf :default [node] (atom? node)) (defmethod get-child :default [parent index] - (nth parent index)) + (if (set? parent) +(nth (seq parent) index) +(nth parent index))) (defmethod get-child-count :default [parent] (count parent)) --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Stack overflow problem
When I learn a new language, one of the programs I like to write as an
excercise is the n-queens problem (http://en.wikipedia.org/wiki/
8_queens). I wrote the program below which runs correctly. Using depth-
first search, I have used it to find the solutions for board sizes up
to 11 (after which it begins taking a lot of time).
But when I use breadth-first search it gives a stack overflow error at
boardsize 7. All recursive calls in the code are done using recur at
tail positions, and it is not clear to me what could otherwise cause
this. Does anyone have a suggestion how to track down the cause of
this stack overflow?
- code
(def dim 6)
(def numsqrs (* dim dim))
(def queen \*)
(def empty-sqr \.)
;; a state in this program is nothing more
;; than a list of positions on the board
;; returns true when placing a queen on both p1 and p2 is disallowed
(defn conflict? [p1 p2]
(let [x1 (rem p1 dim)
x2 (rem p2 dim)
y1 (quot p1 dim)
y2 (quot p2 dim)]
(or
(== x1 x2)
(== y1 y2)
;; diagonals
(let [dx (- x2 x1)
dy (- y2 y1)]
(or (== dx dy)
(== (- dx) dy))
(defn remove-conflicted [p ps]
(remove #(conflict? p %) ps))
;; returns a list of all squares where a queen can be placed in given
state
(defn get-safe-squares [state]
(loop [safe (range (inc (first state)) numsqrs), s state]
(when-not (empty? safe)
(if-not (empty? s)
(recur (remove-conflicted (first s) safe) (rest s))
safe
;; given a state with n queens, returns all possible states with n+1
queens
(defn children [state]
(if (empty? state)
(map #(list %) (range numsqrs))
(when ( (count state) dim)
(map #(conj state %) (get-safe-squares state)
(defn add-children [searchtype statelist]
(let [c (children (first statelist))
s (rest statelist)]
(cond
(= searchtype :breadth-first) (concat s c)
(= searchtype :depth-first) (concat c s
(defn search
([searchtype] (search searchtype (children ()) 0 0))
([searchtype statelist n found]
(if-not (empty? statelist)
(let [s (first statelist)
is-solution (= (count s) dim)
fnd (if is-solution (inc found) found)]
(when is-solution
(println (format Solution: %d, queens at: %s,
searched: %d fnd
s (inc n
;(print-state s))
(recur searchtype (add-children searchtype
statelist) (inc n)
fnd))
{:searched n :found found})))
(search :breadth-first)
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups
Clojure group.
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Getting a result from a swing JDialog
Hi all, I was wanting to create a dialog box in a (predominantly command-line) application where the action of the user on the dialog box is returned to the code that requested the dialog so we can branch based on the selection. It seems the most natural way of doing this in a functional language is to block until the dialog box is closed and then return a value, rather than messing with mutable state. This fits in well with what I want to happen in my program. I can do this quite easily with a JOptionPane, which has the right semantics for me, and can return a single value to indicate what option was chosen. So far so good. However, if I want more control over the layout and content of the dialog, I seem to be best served by building it myself out of a JDIalog [1]. I've got code that creates the JDialog and then blocks until it is closed, which I can control with a button and an ActionListener in the obvious way. However, the snag is that it doesn't return the outcome. The interface of JDialog seems to be built around the idea of having mutable objects and state, and having an action listener that can mutate the object and a getter method to find the value assigned in the listener. I imagine I can get round this by writing a thin wrapper for the JDialog that will handle the state in Java, but is there a pure Clojure way to do this kind of thing? [2] If not, is this (unlikely) a general problem with GUI programming in functional languages or (most likely, I assume) a paradigm mismatch between Swing and functional languages. If the latter, would the Clojure community be well-served by a standard library of shims for making Swing fit better into the functional mould? Tim [1] My experience of Swing is minimal, so I'm ready to be corrected if this turns out to be terribly naive. [2] Aside from unscalable hacks like having a package-level mutable ref that can be updated from within a listener --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
A pipe macro for left-to-right coll streams
Hi, I want to suggest a pipe macro for dealing with collection streams, as a one-line variation on the built in - macro. Instead of writing a nested stream like this: ; Take the first 3 elements of the odd numbers in the range 1 to 20 (take 3 (filter odd? (range 1 20))) you can write this: ; Take the range 1 to 20, filter the odd numbers, then take the first 3 (pipe (range 1 20) (filter odd?) (take 3)) I think both forms have their place. The piped form seems useful when you want to emphasise the collection, or when the chain gets very long. It's also close to how I'd draw the chain on a whiteboard or describe it in speech, and helps me to reason about the chain from left to right in small chunks. The difference with - is this: (- x (f a b)) = (f x a b) (pipe x (f a b)) = (f a b x) The definition is the equivalent of the - macro (defined in core.clj, line 984), swapping ~@(rest form) ~x to ~x ~@(rest form): (defmacro pipe Threads the expr through the forms. Inserts x as the last item in the first form, making a list of it if it is not a list already. If there are more forms, inserts the first form as the last item in second form, etc. ([x form] (if (seq? form) `(~(first form) ~@(rest form) ~x) (list form x))) ([x form more] `(pipe (pipe ~x ~form) ~...@more))) I've seen pipe written as a function with the use of reader macros, or as macros built from scratch. I'm putting this one forward because the tiny change in intention from - is reflected as a tiny delta in the code. Cheers, Matt --~--~-~--~~~---~--~~ 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 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: Discarding entire transactions
(def a (ref 1)) (def b (ref 1)) ; Do these concurrently, either from separate agents or using pmap (dosync (commute b error-throwing-fn a)) (dosync (commute a + @b)) I want to have the option to abort the first transaction without rolling back the second. Based on what you said, if the first transaction is aborted but the second is not then no matter what a's value will be 2 and b's value will be 1, correct? That's correct. --~--~-~--~~~---~--~~ 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 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: Discarding entire transactions
On Sun, Feb 8, 2009 at 12:23 PM, Anand Patil anand.prabhakar.pa...@gmail.com wrote: Hello again, In my application, I'll frequently want to quickly discard all the changes made during a transaction involving many refs. I don't want to force the refs to roll back to their values at the beginning of the transaction, I just want to end the transaction immediately and skip the write stage; updates made in other transactions should still 'stick'. What's the most efficient way to do this? Thanks again! Anand Refs don't roll back their values to the beginning of the transaction. Let say I'm moving money from account A to Account B. Account B has $1000 at the beginning of the transaction. I'm taking $200 from account A and put it into account B. Therefore at the end of my transaction account be should have $1200. However, when the transaction tries to put this result into B it discovers that it has now $1500 in it. This mean that another transaction changed the value first. I clearly can't overwrite this with $1200 otherwise some money would have disappeared! So the STM decide the transaction actually never took place. It doesn't revert B to the beginning of the transaction it just forgot it computed $1200. So the transaction is restarted. This time, it finds out account B should have $1700. If account B still have $1500 then its value will be updated. The STM probably already work as you'd wish. --~--~-~--~~~---~--~~ 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 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: Datalog update
Stratified negation is working and in trunk. I have some cool ideas of a simple, but powerful, way to implement evaluable predicates. They'll likely make it in by midweek. The the hard part (magic sets) begins. On Feb 8, 11:43 am, Jeffrey Straszheim straszheimjeff...@gmail.com wrote: I now have recursive queries working. My next 3 milestones are stratified negation, evaluable predicates, and then some version of magic sets optimization. But now, as long as your queries are non-negated it is working. http://code.google.com/p/clojure-datalog/ --~--~-~--~~~---~--~~ 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 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: Stack overflow problem
Perhaps you are forcing a very long lazy list?
Try (.printStackTrace *e)
On Sun, Feb 8, 2009 at 9:41 AM, jodocus rjek...@gmail.com wrote:
When I learn a new language, one of the programs I like to write as an
excercise is the n-queens problem (http://en.wikipedia.org/wiki/
8_queens http://en.wikipedia.org/wiki/%0A8_queens). I wrote the program
below which runs correctly. Using depth-
first search, I have used it to find the solutions for board sizes up
to 11 (after which it begins taking a lot of time).
But when I use breadth-first search it gives a stack overflow error at
boardsize 7. All recursive calls in the code are done using recur at
tail positions, and it is not clear to me what could otherwise cause
this. Does anyone have a suggestion how to track down the cause of
this stack overflow?
- code
(def dim 6)
(def numsqrs (* dim dim))
(def queen \*)
(def empty-sqr \.)
;; a state in this program is nothing more
;; than a list of positions on the board
;; returns true when placing a queen on both p1 and p2 is disallowed
(defn conflict? [p1 p2]
(let [x1 (rem p1 dim)
x2 (rem p2 dim)
y1 (quot p1 dim)
y2 (quot p2 dim)]
(or
(== x1 x2)
(== y1 y2)
;; diagonals
(let [dx (- x2 x1)
dy (- y2 y1)]
(or (== dx dy)
(== (- dx) dy))
(defn remove-conflicted [p ps]
(remove #(conflict? p %) ps))
;; returns a list of all squares where a queen can be placed in given
state
(defn get-safe-squares [state]
(loop [safe (range (inc (first state)) numsqrs), s state]
(when-not (empty? safe)
(if-not (empty? s)
(recur (remove-conflicted (first s) safe) (rest s))
safe
;; given a state with n queens, returns all possible states with n+1
queens
(defn children [state]
(if (empty? state)
(map #(list %) (range numsqrs))
(when ( (count state) dim)
(map #(conj state %) (get-safe-squares state)
(defn add-children [searchtype statelist]
(let [c (children (first statelist))
s (rest statelist)]
(cond
(= searchtype :breadth-first) (concat s c)
(= searchtype :depth-first) (concat c s
(defn search
([searchtype] (search searchtype (children ()) 0 0))
([searchtype statelist n found]
(if-not (empty? statelist)
(let [s (first statelist)
is-solution (= (count s) dim)
fnd (if is-solution (inc found) found)]
(when is-solution
(println (format Solution: %d, queens at:
%s, searched: %d fnd
s (inc n
;(print-state s))
(recur searchtype (add-children searchtype
statelist) (inc n)
fnd))
{:searched n :found found})))
(search :breadth-first)
--~--~-~--~~~---~--~~
You received this message because you are subscribed to the Google Groups
Clojure group.
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-~--~~~~--~~--~--~---
Re: Stack overflow problem
In fact, try this:
(defn add-children [searchtype statelist]
(let [c (children (first statelist))
s (rest statelist)]
(cond
(= searchtype :breadth-first) (doall (concat s c))
(= searchtype :depth-first) (doall (concat c s)
The doall forces the lists then and there.
On Sun, Feb 8, 2009 at 7:56 PM, Jeffrey Straszheim
straszheimjeff...@gmail.com wrote:
Perhaps you are forcing a very long lazy list?
Try (.printStackTrace *e)
On Sun, Feb 8, 2009 at 9:41 AM, jodocus rjek...@gmail.com wrote:
When I learn a new language, one of the programs I like to write as an
excercise is the n-queens problem (http://en.wikipedia.org/wiki/
8_queens http://en.wikipedia.org/wiki/%0A8_queens). I wrote the program
below which runs correctly. Using depth-
first search, I have used it to find the solutions for board sizes up
to 11 (after which it begins taking a lot of time).
But when I use breadth-first search it gives a stack overflow error at
boardsize 7. All recursive calls in the code are done using recur at
tail positions, and it is not clear to me what could otherwise cause
this. Does anyone have a suggestion how to track down the cause of
this stack overflow?
- code
(def dim 6)
(def numsqrs (* dim dim))
(def queen \*)
(def empty-sqr \.)
;; a state in this program is nothing more
;; than a list of positions on the board
;; returns true when placing a queen on both p1 and p2 is disallowed
(defn conflict? [p1 p2]
(let [x1 (rem p1 dim)
x2 (rem p2 dim)
y1 (quot p1 dim)
y2 (quot p2 dim)]
(or
(== x1 x2)
(== y1 y2)
;; diagonals
(let [dx (- x2 x1)
dy (- y2 y1)]
(or (== dx dy)
(== (- dx) dy))
(defn remove-conflicted [p ps]
(remove #(conflict? p %) ps))
;; returns a list of all squares where a queen can be placed in given
state
(defn get-safe-squares [state]
(loop [safe (range (inc (first state)) numsqrs), s state]
(when-not (empty? safe)
(if-not (empty? s)
(recur (remove-conflicted (first s) safe) (rest s))
safe
;; given a state with n queens, returns all possible states with n+1
queens
(defn children [state]
(if (empty? state)
(map #(list %) (range numsqrs))
(when ( (count state) dim)
(map #(conj state %) (get-safe-squares state)
(defn add-children [searchtype statelist]
(let [c (children (first statelist))
s (rest statelist)]
(cond
(= searchtype :breadth-first) (concat s c)
(= searchtype :depth-first) (concat c s
(defn search
([searchtype] (search searchtype (children ()) 0 0))
([searchtype statelist n found]
(if-not (empty? statelist)
(let [s (first statelist)
is-solution (= (count s) dim)
fnd (if is-solution (inc found) found)]
(when is-solution
(println (format Solution: %d, queens at:
%s, searched: %d fnd
s (inc n
;(print-state s))
(recur searchtype (add-children searchtype
statelist) (inc n)
fnd))
{:searched n :found found})))
(search :breadth-first)
--~--~-~--~~~---~--~~
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-~--~~~~--~~--~--~---
Re: Getting a result from a swing JDialog
A JDialog is going to run on the GUI thread and you can't change that. There are various concurrency tools in Java that will give you what you want. The easiest is to wait create a SynchronousQueue. Check the Java API docs. On Sat, Feb 7, 2009 at 6:15 PM, Tim Martin t...@asymptotic.co.uk wrote: Hi all, I was wanting to create a dialog box in a (predominantly command-line) application where the action of the user on the dialog box is returned to the code that requested the dialog so we can branch based on the selection. It seems the most natural way of doing this in a functional language is to block until the dialog box is closed and then return a value, rather than messing with mutable state. This fits in well with what I want to happen in my program. I can do this quite easily with a JOptionPane, which has the right semantics for me, and can return a single value to indicate what option was chosen. So far so good. However, if I want more control over the layout and content of the dialog, I seem to be best served by building it myself out of a JDIalog [1]. I've got code that creates the JDialog and then blocks until it is closed, which I can control with a button and an ActionListener in the obvious way. However, the snag is that it doesn't return the outcome. The interface of JDialog seems to be built around the idea of having mutable objects and state, and having an action listener that can mutate the object and a getter method to find the value assigned in the listener. I imagine I can get round this by writing a thin wrapper for the JDialog that will handle the state in Java, but is there a pure Clojure way to do this kind of thing? [2] If not, is this (unlikely) a general problem with GUI programming in functional languages or (most likely, I assume) a paradigm mismatch between Swing and functional languages. If the latter, would the Clojure community be well-served by a standard library of shims for making Swing fit better into the functional mould? Tim [1] My experience of Swing is minimal, so I'm ready to be corrected if this turns out to be terribly naive. [2] Aside from unscalable hacks like having a package-level mutable ref that can be updated from within a listener --~--~-~--~~~---~--~~ 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 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: print/println vs. pr/prn
On Sun, Feb 8, 2009 at 10:16 AM, Mark Volkmann r.mark.volkm...@gmail.com wrote: I know print and println are intended for human readable output, whereas pr and prn produce output that can be read by the Clojure reader. I'm trying to find some cases where these differ. So far I've only found String where print/println output the value without quotes and pr/prn include the quotes. What are some other kinds of objects where the output differs? The only other I see is Character: user= (prn \tab \x end) \tab \x end nil user= (println \tab \x end) x end nil --Chouser --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
Clojure, Slime and multiple file projects
Hi folks, I'm getting to the stage on a Clojure project that I want to start breaking the code into multiple files. My primary environment is Emacs Slime and interactive development. Is there a standard way for me to load all of my project's files into the running VM? Right now I manually go to each file load it. I guess I could also write a little function that loaded all the files in the correct order, but if there is an actual framework tool (like ASDF) then I would try to use that. Cheers, Brad --~--~-~--~~~---~--~~ 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 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, Slime and multiple file projects
On Feb 9, 1:05 am, Bradbev brad.beveri...@gmail.com wrote: Hi folks, I'm getting to the stage on a Clojure project that I want to start breaking the code into multiple files. My primary environment is Emacs Slime and interactive development. Is there a standard way for me to load all of my project's files into the running VM? Right now I manually go to each file load it. I guess I could also write a little function that loaded all the files in the correct order, but if there is an actual framework tool (like ASDF) then I would try to use that. I use the time-honored lisp-hacker method of building a load-file. I have a clojure source file that sits at the root of a project, named build.clj. It contains a few simple functions that load project files in order. As I get closer to deployment, I start work on functions to build the reployable versions of things. If you want something more like make or ant or ASDF, you might look at Lancet, from the Programming Clojure book. I haven't used it, but I do belevei it's intended to scrath your itch. --~--~-~--~~~---~--~~ 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 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 -~--~~~~--~~--~--~---
