Scoping question
Is there any practical difference between: (let [x 2] (defn f [] x)) and (def f (let [x 2] (fn [] x)))? --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
Rich Hickey interview from QCon London
For those without a Google Alert set up for Clojure: "In this interview taped at QCon London 2009 Rich Hickey talks about Clojure, shortly before the 1.0 release." http://www.infoq.com/news/2009/05/hickey-clojure 42 minute video: http://www.infoq.com/interviews/hickey-clojure --Steve smime.p7s Description: S/MIME cryptographic signature
Clojure equivalent to Ruby's ERB
Hopefully this doesn't get me booed off the message board but is there a Clojure equivalent to Ruby's ERB? I'm try to use Clojure to perform code generation and, while it makes for an excellent language to write a parser in, I can't quite figure out the best way to actually template out the code. Thanks for any help, Mark P.S. Rich -- if you read this, Clojure is terrific. --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
Exit from clojure box?
Hi everyone, I have just started learning Clojure, and I found Clojure Box (http:// clojure.bighugh.com/) to be an easy installation for that. Unfortunately, I am not sure about the right way to exit from the prompt. After starting Clojure Box and using the prompt (possibly including loading and saving files), when I try to exit using C-x C-c I get the message "Active processes exist; kill them and exit anyway? (yes or no)" which tries to kill SLIME Lisp and inferior-lisp buffers. Answering yes will kill them and exit, but is this the proper way, or is there a more sensible one? Many thanks in advance, Muhammad Alkarouri --~--~-~--~~~---~--~~ 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: Exit from clojure box?
> I have just started learning Clojure, and I found Clojure Box (http:// > clojure.bighugh.com/) to be an easy installation for that. > Unfortunately, I am not sure about the right way to exit from the > prompt. > After starting Clojure Box and using the prompt (possibly including > loading and saving files), when I try to exit using C-x C-c I get the > message "Active processes exist; kill them and exit anyway? (yes or > no)" which tries to kill SLIME Lisp and inferior-lisp buffers. > Answering yes will kill them and exit, but is this the proper way, or > is there a more sensible one? In the SLIME REPL, press , (comma) and then type 'quit' and press Enter. That'd close your REPL gracefully after which you can exit Emacs by pressing C-x C-c. Regards, BG -- Baishampayan Ghose oCricket.com signature.asc Description: OpenPGP digital signature
Re: Scoping question
On May 27, 4:12 am, Mark Engelberg wrote: > Is there any practical difference between: > > (let [x 2] > (defn f [] x)) > > and > > (def f (let [x 2] (fn [] x)))? No, are you experiencing one? Rich --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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 equivalent to Ruby's ERB
On May 27, 4:47 am, markgunnels wrote: > Hopefully this doesn't get me booed off the message board but is there > a Clojure equivalent to Ruby's ERB? I don't think there is a Clojure equivalent (i.e. for general purpose text generation), but given Clojure's great Java integration you could easily use e.g. Freemarker. An advantage here is that you can use Clojure datastructures (think PersistentHashMap, PersistentVector) as Freemarker models. There is also StringTemplate which is a functional approach to templating which might match Clojure better (but I haven't tried out ST). If you are doing HTML/XML generation I think there are many pure- Clojure options... /Karl --~--~-~--~~~---~--~~ 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: Scoping question
No, I was just worried that using def/defn not at the top level, but inside a let, might have unforeseen consequences. On Wed, May 27, 2009 at 3:48 AM, Rich Hickey wrote: > No, are you experiencing one? > --~--~-~--~~~---~--~~ 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: svn r1370 appears to have broken binding
Thanks for the help and your feedback, Steve! Clojure needs some unit tests and I like writing them, so it is a win- win situation :-) Yes, this is our first test in clojure-contrib.test-clojure.vars. I checked it in together with other changes as revision 846. Frantisek On May 26, 9:27 pm, "Stephen C. Gilardi" wrote: > Hi Frantisek! > > On May 25, 2009, at 7:11 AM, Frantisek Sodomka wrote: > > > (def a) > > (deftest test-binding > > (are (= _1 _2) > > (binding [a 4] a) 4 ; regression in Clojure SVN r1370 > > )) > > I see those tests going in over time... Thanks so much for making them! > > The checkin notes for this change mention "top level". I suspect > that's related to why the test you posted gave a false pass. > > We can use eval to bring the test up to the top level: > > (def a) > (deftest test-binding > (are (= _1 _2) > (eval `(binding [a 4] a)) 4 ; regression in Clojure SVN > r1370 > )) > > This passes with r1375 and fails with r1370. > > Will this be our first test in clojure-contrib.test-clojure.vars? > > Feel free to check this in or let me know if you'd like me to. > > Thanks, > > --Steve > > smime.p7s > 3KViewDownload --~--~-~--~~~---~--~~ 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: ns :use with :rename
> Here's the correct syntax:
>
> (ns namespace
>(:use [other-namespace :rename {existing newname}]))
aha, brackets. Is there a plan to flesh out the API page to have more
examples of things like that? As it stands, I think the API page is
probably great for somebody who needs a reminder, but for a newbie, it
could probably be a little more friendly.
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Re: Clojure equivalent to Ruby's ERB
Hi there
Find attached some code that uses apache velocity for command line based
processing, i.e. it's not setup for servlets; i use this as an offline
pre processor for web sites.
It does hierarchical templating of files in a source directory and
copies to a target directory. The templating maps are contained in (by
default) __pp.clj files in the source tree. Further, your __pp.clj maps
can also contain functions for dynamically populating the template.
The nice thing is that each directory can contain it's own __pp.clj file
each of which can override it's parent definitions (in a zope like
'aquisition').
Processing can also be controlled by passing command line arguments
which are added to the templates top level context.
It's not documented, but if anyone is interested I can do some.
cheers
bd
On Tue, 2009-05-26 at 19:47 -0700, markgunnels wrote:
> Hopefully this doesn't get me booed off the message board but is there
> a Clojure equivalent to Ruby's ERB? I'm try to use Clojure to perform
> code generation and, while it makes for an excellent language to write
> a parser in, I can't quite figure out the best way to actually
> template out the code.
>
> Thanks for any help,
> Mark
>
> P.S. Rich -- if you read this, Clojure is terrific.
>
> >
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(ns ipowerhouse.live
(:import java.io.File
(org.apache.velocity VelocityContext Template)
(org.apache.velocity.app Velocity)
(org.apache.velocity.app.event InvalidReferenceEventHandler EventCartridge)
java.util.Properties
(org.apache.commons.io FileUtils FilenameUtils))
(:use ipowerhouse.utils.useful))
(declare *pp*)
(declare *extensions*)
(declare *src*)
(declare *dst*)
(declare *ignore*)
(declare *verbose*)
(def *rvc* (VelocityContext.))
(def Rcontexts (ref (hash-map)))
(def Rdirty (ref (vector)))
(defn printIt [& m]
(if (= *verbose* "yes")
(println m)))
; event handler stuff unused as of now ...
(comment
(defn getIRH []
(proxy [InvalidReferenceEventHandler] []
(invalidGetMethod [ctx rf obj prop info]
(printIt "**get:" info)
)
(invalidSetMethod [ctx left right info]
(printIt "**set:" info)
)
(invalidMethod [ctx rf obj method info]
(printIt "**method:" info)
)))
(defn addEventHandler [vc]
(let [ec (EventCartridge.)]
(.addEventHandler ec (getIRH))
(.attachToContext ec vc)))
(addEventHandler *rvc*)
)
(defn removeSrc [#^File f]
(let [p (.getPath f)
ctop (count *src*)]
(subs p ctop)))
(defn check-dirty [p fileName]
(let [src (File. (str *src* "/" p fileName))
dst (File. (str *dst* "/" p fileName))]
(when (and (.exists src) (.exists dst))
(when (FileUtils/isFileNewer src dst)
(printIt src "is dirty")
(dosync
(commute Rdirty conj p))
(defn dirty? [f]
(some #(.startsWith f %1) @Rdirty))
(defn forced? []
(.containsKey *rvc* "force"))
(defn getDir [f]
(FilenameUtils/getPath (FilenameUtils/normalizeNoEndSeparator f)))
(defn closestContext [curdir]
(loop [d curdir]
(let [p (getDir d)]
(if (contains? @Rcontexts p)
(do
;(printIt "ctx for " curdir " is " p)
(@Rcontexts p))
(if (= p "")
*rvc*
(recur p))
;(def getClosestContext (memoize MgetClosestContext))
(defn keyCheck [k]
(if (keyword? k) (name k) k))
(defn keywordsToStrings [z]
(if (map? z)
(reduce (fn [a k] (assoc a (keyCheck k) (keywordsToStrings (z k
{} (keys z))
z))
(defn execute [f prms]
(if (fn? f) (f prms) f))
(defn mapIntoContext [m context]
(let [conv (keywordsToStrings m)]
(doseq [[k v] conv]
(.put context k v)) context))
(defn construct [#^File f]
"this only checks dirs where *pp* are actually present"
(let [fr (java.io.FileReader. f)
p (removeSrc f)
ctxKey (getDir p)]
(if-not (contains? @Rcontexts ctxKey)
(let [
vc (if (= ctxKey "")
(VelocityContext. *rvc*)
(VelocityContext. (closestContext p)))]
(let [m (load-reader fr)]
(when m
(let [conv (keywordsToStrings m)
tmpParams { :parentFile (.getParentFile f)
:context vc
:uri p }]
(reduce (fn [a k] (.put a k (execute (conv k) tmpParams)) a) vc (keys conv)
(check-dirty ctxKey (str "/" *pp*))
(dosync
(alter Rcontexts assoc ctxKey vc))
(defn context[top]
(let [
pps (filter #(re-find (re-pattern (str *pp* "$")) (.getAbsolutePath %1))
(file-seq (java.io.File. top)))
pathlen (fn [f]
(.length (.getAbsolutePath f)))]
(doseq [s (sort-by pathlen pps)]
(construct s
(defn newer? [srcf dstf] (FileUtils/
Re: svn r1370 appears to have broken binding
On May 27, 7:59 am, Frantisek Sodomka wrote: > Thanks for the help and your feedback, Steve! > > Clojure needs some unit tests and I like writing them, so it is a win- > win situation :-) > Let me add my thanks as well - this is a great (and otherwise thankless :) contribution. I also wanted to let you know: I'm running your tests, so your work is not in vain. Many thanks, Rich --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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: Scoping question
It seems to me that the first would be immune to redefining what closure/core.let means at the point where f is invoked, while the second one would not be. I was unable to actually redefine closure/core.let - probably because it is a macro. But some function was used in place of let, than it could be rebound. Or am I betraying my total luck of understanding? :) Thanks, Boris On Wed, May 27, 2009 at 6:48 AM, Rich Hickey wrote: > > > > On May 27, 4:12 am, Mark Engelberg wrote: >> Is there any practical difference between: >> >> (let [x 2] >> (defn f [] x)) >> >> and >> >> (def f (let [x 2] (fn [] x)))? > > No, are you experiencing one? > > Rich > > > --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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: Scoping question
On May 27, 2009, at 17:11, Boris Mizhen - 迷阵 wrote: > It seems to me that the first would be immune to redefining what > closure/core.let means at the point where f is invoked, while the > second one would not be. No. Both definitions create a closure inside which x has the fixed value 2. When f is invoked, neither x nor let can change that any more. Moreover, given that let is a macro, changing its definition after the evaluation of the initial let form can never make a difference. > I was unable to actually redefine closure/core.let - probably because > it is a macro. But some function was used in place of let, than it > could be rebound. If let were a function, then the two forms would be different even without any redefinition, as the function would be called with different arguments in the two cases. Konrad. --~--~-~--~~~---~--~~ 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: Feedback on new persistentmatrix datatype
On May 27, 2009, at 1:03, aperotte wrote: > I think I understand your point now. You would like the indexing to > match the implicit dimension order of the nested structure. Right. > I was also concerned about storage order because I wanted to at some > point integrate this datastructure with colt or parallel colt and the > incanter library. Both handle only 1D and 2D arrays, so they look rather limited. But compatibility for those is of course a nice feature to have. > I thought the idea was that if while > stepping through the backing array the right-most index varied fastest > you were in column-major and if the left-most index varied fastest you > were in row-major. True, but as you say this is ultimately a feature of the backing array, not of the client interface to the N-D array. > My main reasoning for doing things this way is so that dimension > numbers are stable through data structure building. They are always stable at one end and not on the other. To me it doesn't really matter which end gets to be variable. > I was considering the slices of the outer-most dimension of the nested > array (or the right-most dimension of the matrix) to be the "elements" > of the collection when dealing with it in a lispy way. If I start > with a 2 dimensional structure with elements in the 0 and 1 > dimensions, and I conj it with another 2 dimensional structure, I > would not like to see the two structures juxtaposed along a new 0 > dimension. I would rather they maintain their original dimensions and > be juxtaposed along a new dimension, 2. That's certainly a nice operation to have, but I wouldn't call it conj, because conj takes a collection and an element, whereas what you describe is the combination of two elements into a new collection. One way to create a higher-dimensional collection would be to first add a new dimension to the future elements (this is a low-cost operation, as only the shape information is updated), and then use concat or an n-d generalization of it. > The two ways of doing this that we're describing are very similar. I > think in what you're describing, the outermost layer of the nested > structure that goes into the constructor becomes the left-most index > and nth operates on that index. In what I'm describing, the outermost > layer becomes the right-most index and nth operates on that index. Right. > The sole reason for this is to maintain stable dimension numbers when > indexing, but since nth operates on the last dimension it maintains > the same semantics as what your describing (as well as the same > semantics as vectors). I admit it might be a bit confusing to have > nth operate in the opposite direction as index, but I think keeping > stable dimension numbers is a worthwhile reason. > > Do you disagree? Let's say my priorities are different: I consider it more important to have consistent index order across all operations, and I don't attach much importance to which end of the shape array remains stable when higher-dimensional structures are built. Konrad. --~--~-~--~~~---~--~~ 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: Scoping question
Makes sense, thanks! On Wed, May 27, 2009 at 11:30 AM, Konrad Hinsen wrote: > > On May 27, 2009, at 17:11, Boris Mizhen - 迷阵 wrote: > >> It seems to me that the first would be immune to redefining what >> closure/core.let means at the point where f is invoked, while the >> second one would not be. > > No. Both definitions create a closure inside which x has the fixed > value 2. When f is invoked, neither x nor let can change that any more. > > Moreover, given that let is a macro, changing its definition after > the evaluation of the initial let form can never make a difference. > >> I was unable to actually redefine closure/core.let - probably because >> it is a macro. But some function was used in place of let, than it >> could be rebound. > > If let were a function, then the two forms would be different even > without any redefinition, as the function would be called with > different arguments in the two cases. > > Konrad. > > > > > --~--~-~--~~~---~--~~ 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: ns :use with :rename
+1 for better info on :use/:require. I find I tend to go digging into
the clojure-contrib source for decent examples just because I'm not
sure where else to look.
On May 27, 11:03 am, tsuraan wrote:
> > Here's the correct syntax:
>
> > (ns namespace
> > (:use [other-namespace :rename {existing newname}]))
>
> aha, brackets. Is there a plan to flesh out the API page to have more
> examples of things like that? As it stands, I think the API page is
> probably great for somebody who needs a reminder, but for a newbie, it
> could probably be a little more friendly.
--~--~-~--~~~---~--~~
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Re: Clojure equivalent to Ruby's ERB
Thanks. This looks awesome. On May 27, 10:28 am, ritchie turner wrote: > Hi there > > Find attached some code that uses apache velocity for command line based > processing, i.e. it's not setup for servlets; i use this as an offline > pre processor for web sites. > > It does hierarchical templating of files in a source directory and > copies to a target directory. The templating maps are contained in (by > default) __pp.clj files in the source tree. Further, your __pp.clj maps > can also contain functions for dynamically populating the template. > > The nice thing is that each directory can contain it's own __pp.clj file > each of which can override it's parent definitions (in a zope like > 'aquisition'). > > Processing can also be controlled by passing command line arguments > which are added to the templates top level context. > > It's not documented, but if anyone is interested I can do some. > > cheers > > bd > > On Tue, 2009-05-26 at 19:47 -0700, markgunnels wrote: > > Hopefully this doesn't get me booed off the message board but is there > > a Clojure equivalent to Ruby's ERB? I'm try to use Clojure to perform > > code generation and, while it makes for an excellent language to write > > a parser in, I can't quite figure out the best way to actually > > template out the code. > > > Thanks for any help, > > Mark > > > P.S. Rich -- if you read this, Clojure is terrific. > > > > pp.clj > 6KViewDownload > > __pp.clj > < 1KViewDownload > > __pp.clj > < 1KViewDownload --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
[PATCH] Validating Symbols/Keywords readability
I wrote a patch for issue #13 a few weeks back, but it was right around the 1.0 push, so I didn't want to destabilize things. Now seems like a good time to discuss it: http://code.google.com/p/clojure/issues/detail?id=13 This uses the reader to ensure that symbols and keywords have names that are actually readable when created with the "symbol" or "keyword" function. Please let me know if there are any problems with this approach. thanks, Phil --~--~-~--~~~---~--~~ 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: JVM hanging after -main
billh04 wrote: > I think you are responsible for ending the currently running > agents. The usual method is to set up some field which the agents > monitor looking for some value indicating the application is > ending. By "ending currently running agents" do you mean the action run on the agent? My problem doesn't seem to be action-related because when I take out the agents and execute the same code synchronously, the JVM exits as I expect. For the record, I was able to consistently hang the JVM indefinitely from the command line in addition to invocation from cron, contrary to my claim in my other message. I suspect that others are not seeing any issues because most Java environments are persistent. Anyone else scripting with Clojure using agents? Thanks. -Drew --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
Modular Contrib build with Ivy
Dear Clojurians, this is the next iteration of my Ivy experiments to provide a modular build of contrib. With the support of Kresimir Sojat I restructured the build. Previously the different contrib modules were provided as configurations. This is now changed in that every contrib module is also an Ivy module. Each module provides three configurations: compiled providing AOT, source providing the sources and default which extends the other two. lazy-xml also provides a with-xmlpull configuration to suck in the optional xmlpull dependency. To specify eg. a dependency on a pre-compiled c.c.def use: To use the repository add it to your ivysettings.xml: http://kotka.de/ivy/ivysettings.xml"/> Concerning clojure itself I renamed the module from clojure-lang to clojure to match the .pom nomenclature. Feedback appriciated! Sincerely Meikel clojure-ivy2-rev1375.diff Description: Binary data contrib-ivy4-rev845.diff Description: Binary data smime.p7s Description: S/MIME cryptographic signature
Re: Clojure equivalent to Ruby's ERB
I think you could do a hack using macros and eval at runtime in order to expand them into your code, but I think one of the fellas in the chat room said to be wary if that's the only approach I can see to a problem, because it's easy to screw up, and not entirely good practice. Btw, does clojure have string interpolation? --~--~-~--~~~---~--~~ 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 equivalent to Ruby's ERB
On May 26, 10:47 pm, markgunnels wrote: > Hopefully this doesn't get me booed off the message board but is there > a Clojure equivalent to Ruby's ERB? I'm try to use Clojure to perform > code generation I've had success with StringTemplate. Very functional design, easy to call from Clojure. And it's designed for code generation (the ANTLR parser generator). -Stuart Sierra --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
replacing java + xml (possible java1 demo)
wow. the fact that people use java+somehatefullibs+xml and apparently think that is something "good", completely drives me insane. i mean, it isn't just additional bloat, it is more like ackermann-function-scale bloat. gargh! has anybody done something like: 1) convert the bloody XML to Clojure lispy goodness 2) ok well you are done, it is now code! :-} ? ack. barf. --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
Macro Writing Helper?
Hi, I'm trying to write some macro-defining macros, and the recursive backquotes are making my brain spin circles. Is there a macro writing helper so that I can expand my macros level by level and see the intermediate result? I'm using macroexpand-1 right now, but it's not terribly useful as backquotes expand to something nasty. Given: (defmacro mymacro [] `(level1 `(level2))) I would like to see it expanded to: (user/level1 `(level2)) not: (user/level1 (clojure.core/seq (clojure.core/concat (clojure.core/list (quote user/level2) Is there something like this out there? -Patrick --~--~-~--~~~---~--~~ 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: JVM hanging after -main
Hi Drew, I've been trying to recreate your issue (defn forever[x] (while true (Thread/sleep 100) (print \-) (flush))) (let [a (agent 0)] (send (agent 0) forever)) (println (Thread/activeCount) "threads active") (shutdown-agents) (println "I'm here") ;(System/exit 0) Notably shutdown-agents is a non-blocking call, and without the exit the program runs forever. With the exit, for me the program terminates - but I believe this is where the behavior which may vary... something different occurring in your environment to mine - shutodown hooks? JVM? My only other stab in the dark is could your (flush) actually block before System/exit is called? Can you try my example and see if it hangs for you, and/or if there some code you can paste that hangs? Regards, Tim. On May 28, 6:08 am, Drew Raines wrote: > billh04 wrote: > > I think you are responsible for ending the currently running > > agents. The usual method is to set up some field which the agents > > monitor looking for some value indicating the application is > > ending. > > By "ending currently running agents" do you mean the action run on > the agent? My problem doesn't seem to be action-related because when > I take out the agents and execute the same code synchronously, the > JVM exits as I expect. > > For the record, I was able to consistently hang the JVM indefinitely > from the command line in addition to invocation from cron, contrary > to my claim in my other message. I suspect that others are not > seeing any issues because most Java environments are persistent. > Anyone else scripting with Clojure using agents? > > Thanks. > > -Drew --~--~-~--~~~---~--~~ 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: replacing java + xml (possible java1 demo)
Hello, Here's what I've done in times past: (ns process-xml-in-a-file (:require [clojure.zip :as zip]) (:require [clojure.contrib.zip-filter.xml :as zfx]) (:require [clojure.xml :as xml])) ; creating list of all checkable instances (def dev2-cfg-xml (-> "c:/dl/tibsup/Prod_Stg_auto_shutdown/dev2/dev2_config_start.xml" (xml/parse) (zip/xml-zip))) (def instances (fn [cfg-xml] (zfx/xml-> cfg- xml :Phases :Phase :ServiceInstances :Sequence :group :instances zfx/ text))) (instances dev2-cfg-xml) I can't provide dev2_config_start.xml as there's confidential info in the dev2_config_start.xml, and I'm pressed for time. I'm not sure if it's exactly what you had in mind, but I hope it helps nonetheless. Kev On May 28, 10:19 am, Raoul Duke wrote: > wow. the fact that people use java+somehatefullibs+xml and apparently > think that is something "good", completely drives me insane. i mean, > it isn't just additional bloat, it is more like > ackermann-function-scale bloat. gargh! has anybody done something > like: > > 1) convert the bloody XML to Clojure lispy goodness > 2) ok well you are done, it is now code! :-} > > ? > > ack. barf. --~--~-~--~~~---~--~~ 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 -~--~~~~--~~--~--~---
how would I do this functionally? (internally mutable state)
Hi all, I have some ruby code that I'm thinking of porting to clojure, but I'm not sure how to translate this idiom to a functional world: I have objects that are externally immutable, but have internal mutable state they use for optimisation, specifically in this case to defer un-needed calculations. Basically, I have a FileInfo class that wraps a data file, used to compare lots of files on my system. It has an "exact_match" method similar to: def exact_match(other) return false if size != other.size return false if quickhash() != other.quickhash() return hash() != other.hash() end quickhash and hash store their results in instance variables so they only need to do the expensive calculations once - and quite often they never need to get calculated at all; I'm looking for duplicate files, but many files have no duplicate, so probably never need to have their contents hashed. How would I do this in a functional way? My first effort would be something like (defn hash [filename] (memoize (... hash function ...))) but I have a couple of problems with this: - it doesn't seem to store the hash value with the rest of the file information, which feels a bit ugly - I assume it means storing the full filename three times, once in the original file info structure, once in the memoized hash function, and once in the memoized quickhash function. My program struggles to get enough RAM to track as many files as I'd like already - storing the filename multiple times would blow out memory quite badly. I guess I could define a unique key for each filename, and define hash as a function on that key, but then hash would need to be able to access the list of filenames somehow. It's starting to get beyond me - I'm hoping there's a simpler option! Any suggestions? I'd hope this is not an uncommon idiom. - Korny -- Kornelis Sietsma korny at my surname dot com "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: how would I do this functionally? (internally mutable state)
Hello. I am new to clojure, but try it. code: (defn get-size [filename] (println 'size filename) (count filename)) (defn get-quickhash [filename] (println 'quickhash filename) (hash (take 3 filename))) (defn get-hash [filename] (println 'hash filename) (hash filename)) (def get-info (memoize (fn [filename] (map #(% filename) [get-size get-quickhash get-hash] (println "A") (nth (get-info "abc") 0) (nth (get-info "abc") 0) (println "B") (nth (get-info "abc") 0) (nth (get-info "abc") 1) (println "C") (nth (get-info "abc") 0) (nth (get-info "abc") 1) (nth (get-info "abc") 2) (println "D") (nth (get-info "abc") 0) (nth (get-info "abc") 1) (nth (get-info "abc") 2) result: A size abc B quickhash abc C hash abc D For memory efficiency, I suppose you may use state-monads and trie. But it will need a lot of lines of code, and too hard for me. Regards, - Mikio Hokari 2009/5/28 Korny Sietsma : > > Hi all, > > I have some ruby code that I'm thinking of porting to clojure, but I'm > not sure how to translate this idiom to a functional world: > I have objects that are externally immutable, but have internal > mutable state they use for optimisation, specifically in this case to > defer un-needed calculations. > > Basically, I have a FileInfo class that wraps a data file, used to > compare lots of files on my system. > It has an "exact_match" method similar to: > def exact_match(other) > return false if size != other.size > return false if quickhash() != other.quickhash() > return hash() != other.hash() > end > > quickhash and hash store their results in instance variables so they > only need to do the expensive calculations once - and quite often they > never need to get calculated at all; I'm looking for duplicate files, > but many files have no duplicate, so probably never need to have their > contents hashed. > > How would I do this in a functional way? My first effort would be > something like > (defn hash [filename] (memoize (... hash function ...))) > but I have a couple of problems with this: > - it doesn't seem to store the hash value with the rest of the file > information, which feels a bit ugly > - I assume it means storing the full filename three times, once in > the original file info structure, once in the memoized hash function, > and once in the memoized quickhash function. My program struggles to > get enough RAM to track as many files as I'd like already - storing > the filename multiple times would blow out memory quite badly. > > I guess I could define a unique key for each filename, and define hash > as a function on that key, but then hash would need to be able to > access the list of filenames somehow. It's starting to get beyond me > - I'm hoping there's a simpler option! > > Any suggestions? I'd hope this is not an uncommon idiom. > > - Korny > > -- > Kornelis Sietsma korny at my surname dot com > "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: how would I do this functionally? (internally mutable state)
Trouble here is, I only want to call the hash functions as needed. This is doing file differencing, and if I only have a single file of (say) 200 megabytes, I never need to calculate it's hash, as I'll never actually compare it to another file of exactly the same size. - Korny On Thu, May 28, 2009 at 1:25 PM, Mikio Hokari wrote: > > Hello. > > I am new to clojure, but try it. > > code: > > (defn get-size [filename] > (println 'size filename) > (count filename)) > (defn get-quickhash [filename] > (println 'quickhash filename) > (hash (take 3 filename))) > (defn get-hash [filename] > (println 'hash filename) > (hash filename)) > > (def get-info (memoize > (fn [filename] > (map #(% filename) [get-size get-quickhash get-hash] > > (println "A") > (nth (get-info "abc") 0) > (nth (get-info "abc") 0) > (println "B") > (nth (get-info "abc") 0) > (nth (get-info "abc") 1) > (println "C") > (nth (get-info "abc") 0) > (nth (get-info "abc") 1) > (nth (get-info "abc") 2) > (println "D") > (nth (get-info "abc") 0) > (nth (get-info "abc") 1) > (nth (get-info "abc") 2) > > result: > > A > size abc > B > quickhash abc > C > hash abc > D > > > For memory efficiency, I suppose you may use state-monads and trie. > But it will need a lot of lines of code, and too hard for me. > > Regards, > > - > Mikio Hokari > > 2009/5/28 Korny Sietsma : >> >> Hi all, >> >> I have some ruby code that I'm thinking of porting to clojure, but I'm >> not sure how to translate this idiom to a functional world: >> I have objects that are externally immutable, but have internal >> mutable state they use for optimisation, specifically in this case to >> defer un-needed calculations. >> >> Basically, I have a FileInfo class that wraps a data file, used to >> compare lots of files on my system. >> It has an "exact_match" method similar to: >> def exact_match(other) >> return false if size != other.size >> return false if quickhash() != other.quickhash() >> return hash() != other.hash() >> end >> >> quickhash and hash store their results in instance variables so they >> only need to do the expensive calculations once - and quite often they >> never need to get calculated at all; I'm looking for duplicate files, >> but many files have no duplicate, so probably never need to have their >> contents hashed. >> >> How would I do this in a functional way? My first effort would be >> something like >> (defn hash [filename] (memoize (... hash function ...))) >> but I have a couple of problems with this: >> - it doesn't seem to store the hash value with the rest of the file >> information, which feels a bit ugly >> - I assume it means storing the full filename three times, once in >> the original file info structure, once in the memoized hash function, >> and once in the memoized quickhash function. My program struggles to >> get enough RAM to track as many files as I'd like already - storing >> the filename multiple times would blow out memory quite badly. >> >> I guess I could define a unique key for each filename, and define hash >> as a function on that key, but then hash would need to be able to >> access the list of filenames somehow. It's starting to get beyond me >> - I'm hoping there's a simpler option! >> >> Any suggestions? I'd hope this is not an uncommon idiom. >> >> - Korny >> >> -- >> Kornelis Sietsma korny at my surname dot com >> "Every jumbled pile of person has a thinking part >> that wonders what the part that isn't thinking >> isn't thinking of" >> >> > >> > > > > -- Kornelis Sietsma korny at my surname dot com "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: how would I do this functionally? (internally mutable state)
Sounds like a job for lazy-map to me! http://kotka.de/projects/clojure/lazy-map.html On May 28, 11:52 am, Korny Sietsma wrote: > Hi all, > > I have some ruby code that I'm thinking of porting to clojure, but I'm > not sure how to translate this idiom to a functional world: > I have objects that are externally immutable, but have internal > mutable state they use for optimisation, specifically in this case to > defer un-needed calculations. > > Basically, I have a FileInfo class that wraps a data file, used to > compare lots of files on my system. > It has an "exact_match" method similar to: > def exact_match(other) > return false if size != other.size > return false if quickhash() != other.quickhash() > return hash() != other.hash() > end > > quickhash and hash store their results in instance variables so they > only need to do the expensive calculations once - and quite often they > never need to get calculated at all; I'm looking for duplicate files, > but many files have no duplicate, so probably never need to have their > contents hashed. > > How would I do this in a functional way? My first effort would be > something like > (defn hash [filename] (memoize (... hash function ...))) > but I have a couple of problems with this: > - it doesn't seem to store the hash value with the rest of the file > information, which feels a bit ugly > - I assume it means storing the full filename three times, once in > the original file info structure, once in the memoized hash function, > and once in the memoized quickhash function. My program struggles to > get enough RAM to track as many files as I'd like already - storing > the filename multiple times would blow out memory quite badly. > > I guess I could define a unique key for each filename, and define hash > as a function on that key, but then hash would need to be able to > access the list of filenames somehow. It's starting to get beyond me > - I'm hoping there's a simpler option! > > Any suggestions? I'd hope this is not an uncommon idiom. > > - Korny > > -- > Kornelis Sietsma korny at my surname dot com > "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: Exit from clojure box?
On 27/05/2009, Baishampayan Ghose wrote: .. > In the SLIME REPL, press , (comma) and then type 'quit' and press Enter. > > That'd close your REPL gracefully after which you can exit Emacs by > pressing C-x C-c. > > Regards, > BG > > -- Exactly what I wanted. Many thanks! Regards, Muhammad > Baishampayan Ghose > oCricket.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 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 would I do this functionally? (internally mutable state)
Hash calculation runs only when necessary, because Clojure's map function is lazy now. more sample code: (nth (get-info "a.txt") 0) (nth (get-info "b.txt") 0) (nth (get-info "b.txt") 1) result: size a.txt size b.txt quickhash b.txt Output result shows it. When (nth (get-info "a.txt") 0) is evaluated, only get-size function runs. Evaluation of get-quickhash and get-hash is delayed. Eval (nth (get-info "a.txt") 1) cause evaluation of get-quickhash, but not get-hash. 2009/5/28 Timothy Pratley : > > Sounds like a job for lazy-map to me! > http://kotka.de/projects/clojure/lazy-map.html > > > On May 28, 11:52 am, Korny Sietsma wrote: >> Hi all, >> >> I have some ruby code that I'm thinking of porting to clojure, but I'm >> not sure how to translate this idiom to a functional world: >> I have objects that are externally immutable, but have internal >> mutable state they use for optimisation, specifically in this case to >> defer un-needed calculations. >> >> Basically, I have a FileInfo class that wraps a data file, used to >> compare lots of files on my system. >> It has an "exact_match" method similar to: >> def exact_match(other) >> return false if size != other.size >> return false if quickhash() != other.quickhash() >> return hash() != other.hash() >> end >> >> quickhash and hash store their results in instance variables so they >> only need to do the expensive calculations once - and quite often they >> never need to get calculated at all; I'm looking for duplicate files, >> but many files have no duplicate, so probably never need to have their >> contents hashed. >> >> How would I do this in a functional way? My first effort would be >> something like >> (defn hash [filename] (memoize (... hash function ...))) >> but I have a couple of problems with this: >> - it doesn't seem to store the hash value with the rest of the file >> information, which feels a bit ugly >> - I assume it means storing the full filename three times, once in >> the original file info structure, once in the memoized hash function, >> and once in the memoized quickhash function. My program struggles to >> get enough RAM to track as many files as I'd like already - storing >> the filename multiple times would blow out memory quite badly. >> >> I guess I could define a unique key for each filename, and define hash >> as a function on that key, but then hash would need to be able to >> access the list of filenames somehow. It's starting to get beyond me >> - I'm hoping there's a simpler option! >> >> Any suggestions? I'd hope this is not an uncommon idiom. >> >> - Korny >> >> -- >> Kornelis Sietsma korny at my surname dot com >> "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: how would I do this functionally? (internally mutable state)
Yes that is a very elegant solution. For convenience you might want another function: (defn fast-compare "Given two filenames returns true if the files are identical" [fn1 fn2] (let [i1 (get-info fn1), i2 (get-info fn2)] (and (= (first i1) (first i2)) (= (second i1) (second i2)) (= (third i1) (third i2) I wonder if there is a more idiomatic way to compare two lazy sequences... lazily? Regarding lazy-hash-map it just allows you to name the fields instead of using an index, but I think without is better for something that can be expressed like you have. No need for an external dependency. (ooops I called it lazy-map before). Regards, Tim. On May 28, 2:34 pm, Mikio Hokari wrote: > Hash calculation runs only when necessary, because > Clojure's map function is lazy now. > > more sample code: > > (nth (get-info "a.txt") 0) > (nth (get-info "b.txt") 0) > (nth (get-info "b.txt") 1) > > result: > size a.txt > size b.txt > quickhash b.txt > > Output result shows it. > When > (nth (get-info "a.txt") 0) > is evaluated, only get-size function runs. > Evaluation of get-quickhash and get-hash is delayed. > > Eval > (nth (get-info "a.txt") 1) > cause evaluation of get-quickhash, > but not get-hash. > > 2009/5/28 Timothy Pratley : > > > > > Sounds like a job for lazy-map to me! > >http://kotka.de/projects/clojure/lazy-map.html > > > On May 28, 11:52 am, Korny Sietsma wrote: > >> Hi all, > > >> I have some ruby code that I'm thinking of porting to clojure, but I'm > >> not sure how to translate this idiom to a functional world: > >> I have objects that are externally immutable, but have internal > >> mutable state they use for optimisation, specifically in this case to > >> defer un-needed calculations. > > >> Basically, I have a FileInfo class that wraps a data file, used to > >> compare lots of files on my system. > >> It has an "exact_match" method similar to: > >> def exact_match(other) > >> return false if size != other.size > >> return false if quickhash() != other.quickhash() > >> return hash() != other.hash() > >> end > > >> quickhash and hash store their results in instance variables so they > >> only need to do the expensive calculations once - and quite often they > >> never need to get calculated at all; I'm looking for duplicate files, > >> but many files have no duplicate, so probably never need to have their > >> contents hashed. > > >> How would I do this in a functional way? My first effort would be > >> something like > >> (defn hash [filename] (memoize (... hash function ...))) > >> but I have a couple of problems with this: > >> - it doesn't seem to store the hash value with the rest of the file > >> information, which feels a bit ugly > >> - I assume it means storing the full filename three times, once in > >> the original file info structure, once in the memoized hash function, > >> and once in the memoized quickhash function. My program struggles to > >> get enough RAM to track as many files as I'd like already - storing > >> the filename multiple times would blow out memory quite badly. > > >> I guess I could define a unique key for each filename, and define hash > >> as a function on that key, but then hash would need to be able to > >> access the list of filenames somehow. It's starting to get beyond me > >> - I'm hoping there's a simpler option! > > >> Any suggestions? I'd hope this is not an uncommon idiom. > > >> - Korny > > >> -- > >> Kornelis Sietsma korny at my surname dot com > >> "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: how would I do this functionally? (internally mutable state)
On May 27, 2009, at 7:52 PM, Korny Sietsma wrote:
> How would I do this in a functional way? My first effort would be
> something like
>(defn hash [filename] (memoize (... hash function ...)))
> but I have a couple of problems with this:
> - it doesn't seem to store the hash value with the rest of the file
> information, which feels a bit ugly
> - I assume it means storing the full filename three times, once in
> the original file info structure, once in the memoized hash function,
> and once in the memoized quickhash function. My program struggles to
> get enough RAM to track as many files as I'd like already - storing
> the filename multiple times would blow out memory quite badly.
>
> I guess I could define a unique key for each filename, and define hash
> as a function on that key, but then hash would need to be able to
> access the list of filenames somehow. It's starting to get beyond me
> - I'm hoping there's a simpler option!
OK, I'm probably talking out of turn here, but I thought I would share
some of my thoughts.
First of all, though you probably already thought of this, you can
improve time complexity from O(N^2) to O(N log N) if you sort the
files looking for duplicates rather than comparing every file to every
other file. In other words, make a list of files and their hashes, and
sort by the hashes, then walk the list comparing each hash to the
previous hash.
I can think of two ways to do this. The first one I thought of might
be more functional, which would be to successively narrow down a list
of potential duplicates comparison by comparison. It would have a
structure something like this: generate a list of files by size; group
by files of the same size; remove all sublists of length 1 (unique
sizes). Pass that list to a function which generates a list of files
by the quick hash; group by them by it; remove all sublists of length
1. Pass that to a function which does the same thing only with the
more expensive hash. I suspect you could make each of the three steps
a function and then make a fourth function which combines those three
and takes a function as a parameter to produce the hash. Then you
could use the comp function to combine those three functions and
presto, you have your list of duplicates.
Another possible way that more closely resembles what you're doing
right now would be to have a function which looks at a file and lazily
produces the three comparison values, then do the sort/group procedure
with a comparison function that is smart enough to only compare as
much as it has to. I think you could build this with what Mikio was
proposing, because map is lazy.
As another example of this:
(defn get-comparators [str]
(cons (nth str 0)
(lazy-seq (do
(println "Looking at second element")
(Thread/sleep 1000)
(list (nth str 1))
This function returns a list of two values which are just the first
two characters of a string, but it prints a message and waits a second
if the second value in the list is actually forced. If you never look
at the second value, you never pay the penalty for computing it. So
supposing a compare a list of strings which differ on the first
character, it should return immediately without printing anything, and
it does:
user> (sort-by get-comparators #(some (complement zero?) (map compare
%1 %2)) ["ab" "cd" "ef" "gh"])
("ab" "cd" "ef" "gh")
But if some of them have the same first character, it should have a
delay and then return the values:
user> (sort-by get-comparators #(some (complement zero?) (map compare
%1 %2)) ["ab" "cd" "ef" "eg"])
Looking at second element
Looking at second element
("ab" "cd" "ef" "eg")
So you can see that even though it had to use the second values to
compare 'ef' and 'eg', it only had to "compute" their second
characters, not the second characters of any of the other elements.
There is a group-by function in clojure.contrib.seq-utils which would
be of use. Unfortunately I don't see how to do filter with a hash-map
to produce another hash-map. The best I came up with was this:
(def groupings
(clojure.contrib.seq-utils/group-by
#(first (get-comparators %))
["abc" "abd" "hello" "gravy" "stuff" "stripes"]))
(apply hash-map (apply concat (filter (fn [[key value]] (> (count
value) 1)) groupings)))
I don't trust apply, and double apply seems really fishy. I'm probably
missing something obvious there. Also, it would probably be better to
either be able to furnish group-by with a comparison function a la
sort-by or else somehow make lists be instances of comparable to make
this work using get-comparators.
One more note, because you mentioned some concern over having
filenames in memory. I'm not sure but I don't think Java and therefore
Clojure can do this, but in general (at least on Unix-based systems)
you ought to be able to store t
Re: how would I do this functionally? (internally mutable state)
On May 27, 2009, at 11:51 PM, Timothy Pratley wrote: > I wonder if there is a more idiomatic way to compare two lazy > sequences... lazily? I came up with (some (complement zero?) (map compare list-1 list-2)) in my response which missed yours by seconds. :) I'm not sure it's great but it does seem to work. — Daniel Lyons http://www.storytotell.org -- Tell It! --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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: regression
On May 26, 2009, at 10:56 PM, kyle smith wrote: > Thanks for the feedback Daniel, I've incorporated your ideas and re- > uploaded. I'm not sure where you're seeing mutable data structures. I'm hallucinating, that's where. :) > Anyhow, I now only call eval once each time scorer is called, which is > massively faster. > This has allowed for additional testing points, and now I get a > perfect fit in under a minute! > > On a related note, it looks like I've essentially written a better > version of this: > http://www.jakevoytko.com/blog/2008/12/16/evolving-genetic-algorithms-in-lisp/ This is really great! Thanks for sharing it with us! Cool stuff. — Daniel Lyons http://www.storytotell.org -- Tell It! --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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 would I do this functionally? (internally mutable state)
On Thu, May 28, 2009 at 7:58 AM, Daniel Lyons wrote: > > > On May 27, 2009, at 11:51 PM, Timothy Pratley wrote: >> I wonder if there is a more idiomatic way to compare two lazy >> sequences... lazily? > > I came up with (some (complement zero?) (map compare list-1 list-2)) > in my response which missed yours by seconds. :) I'm not sure it's > great but it does seem to work. Except if one of them is a prefix of the other. (some (complement zero?) (map compare [1 2 3] [4 5 6])) => true (some (complement zero?) (map compare [1 2 3] [1 2 3])) => nil (some (complement zero?) (map compare [1 2 3] [1 2])) => nil -- Michael Wood --~--~-~--~~~---~--~~ 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: how would I do this functionally? (internally mutable state)
>> I wonder if there is a more idiomatic way to compare two lazy >> sequences... lazily? You can just use =. (= seq1 seq2) It works lazily. user> (= (iterate inc 0) (map #(do (println %) %) [0 1 2 -3 4 5 6]) ) 0 1 2 -3 false How sweet! 2009/5/28 Daniel Lyons : > > > On May 27, 2009, at 11:51 PM, Timothy Pratley wrote: >> I wonder if there is a more idiomatic way to compare two lazy >> sequences... lazily? > > I came up with (some (complement zero?) (map compare list-1 list-2)) > in my response which missed yours by seconds. :) I'm not sure it's > great but it does seem to work. > > — > Daniel Lyons > http://www.storytotell.org -- Tell It! > > > > > --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com 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 -~--~~~~--~~--~--~---
