Re: [Chicken-users] matchable egg usage question
On Fri, Jan 28, 2011 at 2:21 PM, Alan Post wrote: > I'm trying to use the matchable egg to detect #!key parameters in > functions I've constructed. I have functions that accept multiple > #!key parameters, and I'm not sure how to make the matchable egg > match |(func ... mykey: myvalue ...)|. That is, how to get the > matchable egg to match two parameters anywhere in an input list. Why not use Chicken's builtin #!key handling? (apply (lambda (#!key key1 key2) ;; code using key1 and key2 ...) (list key1: val1 key2: val2)) > This is what I've got so far. I am interested in whether the > #!key paramater 'a' is set to #t: OK, the original point of this style of pattern matching was it was simple and fast - it does a simple linear match against each possible pattern so is as fast as using low-level destructuring and checking (faster if the match library can eliminate common sub-patterns). As soon as you introduce any ambiguity in how a pattern can match the whole process becomes a search algorithm, with backtracking in the general case. So whereas the pattern (a b c) is constant time (O(m) in the pattern size), (a b c ...) is linear (O(n) in the input size), which is fine, but (a b c ... d ...) is O(n^2) in the input size depending on where you choose to split between c and d. And (a b c ... d ... e ...) is O(n^3), etc. Most of the time when you want to use this sort of pattern, you don't want backtracking - you want c to match as many elements as it can and then "commit," and take the rest of the list as d. So if the match doesn't let you express the expensive patterns, you have to iterate over one c at a time: (let lp ((ls ls) (c-ls '()) (match ls ((c . rest) (lp (cdr ls) (cons c c-ls))) (else ;; match d's in remaining ls ...))) This is O(n), and is the same sort of idiom many complex syntax-rules libraries use. So by deliberately limiting match we force people to write faster code. At the same time, it's more verbose code - if you really want a match as powerful as prolog you could implement it and deal with the fact that it can be very slow in some cases. And in that case you will eventually need to add a way to explicitly commit matches (i.e. "cut" in prolog) for decent performance. [I'm not completely consistent in this, though, because the tree patterns I added do in fact require more complex searching and backtracking. But tree searches require this in general.] -- Alex ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Re: matchable egg ticket #487
On Sat, Jan 29, 2011 at 10:52:15AM +0900, Alex Shinn wrote: > On Fri, Jan 28, 2011 at 12:15 AM, Alan Post > wrote: > > I'm only going to get more demanding out of what I'd like match to > > do, I would like the latest version. > > I've updated matchable from the latest upstream, > which includes the fix. > Thank you Alex. I've updated my copy of the matchable egg, removed the workaround I was using to avoid triggering the bug, and after that change my regression tests all pass. -Alan -- .i ko djuno fi le do sevzi ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Re: matchable egg ticket #487
On Fri, Jan 28, 2011 at 12:15 AM, Alan Post wrote: > I'm only going to get more demanding out of what I'd like match to > do, I would like the latest version. I've updated matchable from the latest upstream, which includes the fix. -- Alex ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
[Chicken-users] syntax-case?
Is there a egg for syntax-case macros in Chicken 4? - Joe ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
[Chicken-users] Re: matchable egg usage question
On Thu, Jan 27, 2011 at 10:21:05PM -0700, Alan Post wrote: > I'm trying to use the matchable egg to detect #!key parameters in > functions I've constructed. I have functions that accept multiple > #!key parameters, and I'm not sure how to make the matchable egg > match |(func ... mykey: myvalue ...)|. That is, how to get the > matchable egg to match two parameters anywhere in an input list. > > This is what I've got so far. I am interested in whether the > #!key paramater 'a' is set to #t: > > (use matchable) > > (pretty-print (map > (match-lambda > ((_ 'a: #t . _) '(0 #t)) > ((_ ... 'a: #t) '(1 #t)) > (_ #f)) > '((foo) > (foo bar) > (foo a: #f) > (foo a: #f b: #t) > (foo a: #f b: #t c: #t) > (foo a: #f c: #t b: #t) > (foo b: #t a: #f c: #t) > (foo b: #t c: #t a: #f) > (foo a: #t) > (foo a: #t b: #t) > (foo a: #t b: #t c: #t) > (foo a: #t c: #t b: #t) > (foo b: #t a: #t c: #t) > (foo b: #t c: #t a: #t > (exit) > > This works for every case except when the #!key I want to match > appears in the middle of a list of arguments, as happens in the > second-to-last case I'm trying to match. > > Is there a way to make match work in this case? What pattern > should I add to match values anywhere in the list, not just the > front and end? > I've solved my problem by matching every sublist of my argument list until I find the pattern I'm looking for: (use matchable) (use srfi-1) (define (key-match? pat r) (or r (match pat (`(a: #t . ,_) #t) (_ #f (pretty-print (map (match-lambda ((_ . args) (pair-fold key-match? #f args)) (_ #f)) '((foo) (foo bar) (foo a: #f) (foo a: #f b: #t) (foo a: #f b: #t c: #t) (foo a: #f c: #t b: #t) (foo b: #t a: #f c: #t) (foo b: #t c: #t a: #f) (foo a: #t) (foo a: #t b: #t) (foo a: #t b: #t c: #t) (foo a: #t c: #t b: #t) (foo b: #t a: #t c: #t) (foo b: #t c: #t a: #t (exit) (The match-lambda here is wordier in my real example, I know it is pointless in this example.) -Alan -- .i ko djuno fi le do sevzi ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
[Chicken-users] New python/chicken
This is an improved version of a Chicken REPL embedded in a Python REPL. Variable passing between Python and Chicken is automatic but could probably still use some work. It should be possible to use the Chicken REPL without the need for any special command to interact with Python. If you want to run one command in Chicken and exit back to Python you should use: >>> py_var = c_(once = 1) Otherwise you'll stay in the Chicken REPL until issuing a ,q or (exit) command. Let me know if you notice anything wrong, or would like something else incorporated. I'm planning on starting to wrap this up as a Python egg soon. -Dave scythians.tgz Description: GNU Zip compressed data ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Need help on sxpath/txpath
On Sat, Jan 29, 2011 at 12:11:26AM +0900, Daishi Kato wrote: > > It probably is not a chicken-specific problem because the sxpath > > egg includes an unmodified copy of SSAX. > > Looked at: > diff -rw release/3/sxml-tools/sxml-tools/ release/4/sxpath/trunk/sxml-tools/ > > but, I'm not sure is there's such a big difference. > Furthermode, it's hardly understandable that the newer version is incorrect. > > I don't know what to do... Confirm if it's really a bug against XPath spec? I suck at xpath so I have no idea. You could try the SSAX mailinglist... Cheers, Peter -- http://sjamaan.ath.cx -- "The process of preparing programs for a digital computer is especially attractive, not only because it can be economically and scientifically rewarding, but also because it can be an aesthetic experience much like composing poetry or music." -- Donald Knuth ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Need help on sxpath/txpath
At Fri, 28 Jan 2011 15:34:09 +0100, Peter Bex wrote: > > On Fri, Jan 28, 2011 at 11:27:26PM +0900, Daishi Kato wrote: > > Hi, > > > > I digged into the problem a little more and found something. > > > > In 4.6.0, this is somewhat working: > > #;24> ((sxpath "//table/tr[td[a[contains(href,'&abc=123&')]]]") > > (html->sxml " > href=\"/xxx/yyy/?zzz&abc=123&\">yyy")) > > ((tr (td (a (@ (href "/xxx/yyy/?zzz&abc=123&")) "yyy" > > > > So, I replaced @href with href. > > Is it correct? Maybe not. > > I assume the sxpath egg is incorrect. > > > > Can anybody tell if this is a chicken-specific problem, or > > of sxml-tools at sourceforge? > > It probably is not a chicken-specific problem because the sxpath > egg includes an unmodified copy of SSAX. Looked at: diff -rw release/3/sxml-tools/sxml-tools/ release/4/sxpath/trunk/sxml-tools/ but, I'm not sure is there's such a big difference. Furthermode, it's hardly understandable that the newer version is incorrect. I don't know what to do... Confirm if it's really a bug against XPath spec? Best, Daishi ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Need help on sxpath/txpath
On Fri, Jan 28, 2011 at 11:27:26PM +0900, Daishi Kato wrote: > Hi, > > I digged into the problem a little more and found something. > > In 4.6.0, this is somewhat working: > #;24> ((sxpath "//table/tr[td[a[contains(href,'&abc=123&')]]]") > (html->sxml " href=\"/xxx/yyy/?zzz&abc=123&\">yyy")) > ((tr (td (a (@ (href "/xxx/yyy/?zzz&abc=123&")) "yyy" > > So, I replaced @href with href. > Is it correct? Maybe not. > I assume the sxpath egg is incorrect. > > Can anybody tell if this is a chicken-specific problem, or > of sxml-tools at sourceforge? It probably is not a chicken-specific problem because the sxpath egg includes an unmodified copy of SSAX. Cheers, Peter -- http://sjamaan.ath.cx -- "The process of preparing programs for a digital computer is especially attractive, not only because it can be economically and scientifically rewarding, but also because it can be an aesthetic experience much like composing poetry or music." -- Donald Knuth ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] Need help on sxpath/txpath
Hi, I digged into the problem a little more and found something. In 4.6.0, this is somewhat working: #;24> ((sxpath "//table/tr[td[a[contains(href,'&abc=123&')]]]") (html->sxml "yyy")) ((tr (td (a (@ (href "/xxx/yyy/?zzz&abc=123&")) "yyy" So, I replaced @href with href. Is it correct? Maybe not. I assume the sxpath egg is incorrect. Can anybody tell if this is a chicken-specific problem, or of sxml-tools at sourceforge? Best, Daishi At Sun, 16 Jan 2011 22:32:23 +0900, Daishi Kato wrote: > > Here you go. --daishi > > CHICKEN > (c)2008-2010 The Chicken Team > (c)2000-2007 Felix L. Winkelmann > Version 4.6.0 > linux-unix-gnu-x86 [ manyargs dload ptables ] > compiled 2011-01-11 on spirits (Linux) > > #;1> (use sxpath htmlprag utils) > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/sxpath.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/chicken.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/scheme.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/data-structures.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/srfi-1.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/srfi-13.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/sxpath-lolevel.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/extras.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/ports.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/txpath.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/htmlprag.import.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/sxpath.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/sxpath-lolevel.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/txpath.so ... > ; loading /usr/local/chicken-4.6.0/lib/chicken/5/htmlprag.so ... > ; loading library utils ... > #;2> ((sxpath "//table/tr[td[a[contains(@href,'&abc=123&')]]]") > (html->sxml " href=\"/xxx/yyy/?zzz&abc=123&\">yyy")) > () > #;3> > > > CHICKEN > (c)2008 The Chicken Team > (c)2000-2007 Felix L. Winkelmann > Version 3.2.0 - linux-unix-gnu-x86 [ manyargs dload ptables applyhook ] > SVN rev. 10664 compiled 2008-05-28 on spirits (Linux) > > #;1> (use sxml-tools htmlprag utils) > ; loading /usr/local/chicken-3.2.0/lib/chicken/3/sxml-tools.so ... > ; loading /usr/local/chicken-3.2.0/lib/chicken/3/htmlprag.so ... > ; loading library utils ... > #;2> ((sxpath "//table/tr[td[a[contains(@href,'&abc=123&')]]]") > (html->sxml " href=\"/xxx/yyy/?zzz&abc=123&\">yyy")) > ((tr (td (a (@ (href "/xxx/yyy/?zzz&abc=123&")) "yyy" > #;3> > > > At Sun, 16 Jan 2011 13:27:41 +0100, > Peter Bex wrote: > > > > On Sun, Jan 16, 2011 at 03:49:41PM +0900, Daishi Kato wrote: > > > Hi, > > > > > > I'm porting one of my projects from chicken-3.2.0 to chicken-4.6.0. > > > (And thus found a bug in http-client.) > > > > > > It seems like the previous sxpath doesn't work on the new one. > > > Could anybody help how I can fix this? > > > > > > The sxpath worked on chicken-3.2.0 is something like the following: > > > > > > ((sxpath "//table/tr[td[a[contains(@href,'&abc=123&')]]]") x) > > > > > > On 3.2.0 I used the sxml-tools egg and the sxpath egg on 4.6.0 > > > > What is the error you get? What is the content you run this > > expression on? Can you simplify it to a simple testcase? > > > > My gut feeling is that the & is maybe wrong. Did you try just '&'? > > > > Cheers, > > Peter > > -- > > http://sjamaan.ath.cx > > -- > > "The process of preparing programs for a digital computer > > is especially attractive, not only because it can be economically > > and scientifically rewarding, but also because it can be an aesthetic > > experience much like composing poetry or music." > > -- Donald Knuth > > > > ___ > > Chicken-users mailing list > > Chicken-users@nongnu.org > > http://lists.nongnu.org/mailman/listinfo/chicken-users > > > > ** > > XREA.COM -Free Web Hosting- > > http://www.xrea.com/ > > ** ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
Re: [Chicken-users] chicken slime REPL message
Ah! I was expecting something in the lines of the clojure repl where it echoes the function name and its namespace it lives in. user=> (defn hello [] (println "hi")) #'user/hello On Thu, Jan 27, 2011 at 11:54 AM, David Krentzlin wrote: > -BEGIN PGP SIGNED MESSAGE- > Hash: SHA1 > > Hi, > > yes, this is normal behaviour. What you see is the printable > representation of the return value of the define form. > As you may have guessed, it has none, so it prints #. > Try it with a form that does actually produce a value. > > > cheers david > > > On 27.01.2011 14:40, Joe Python wrote: > > Is it normal behaviour to get the '#' message. > > > > ; SLIME 2010-01-03 > > CSI> (define (hello) > > (display "Hi")) > > # > > CSI> > > > > > > > > ___ > > Chicken-users mailing list > > Chicken-users@nongnu.org > > http://lists.nongnu.org/mailman/listinfo/chicken-users > > -BEGIN PGP SIGNATURE- > Version: GnuPG v1.4.10 (GNU/Linux) > Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ > > iQIcBAEBAgAGBQJNQaMuAAoJEPZusy+CqjZ2KMAQAKMCO6mAlElo+ekRYye2dNWM > 5btGfStkj19jqKjiVSOYMvQMJEPy1op8vmT5Zm5Wolqya0rW7EdmjzwduXp/2SY4 > E51/y5+dza/e9MisIQPYmkkP846/UDcdUvhVBh2lZWdpfFE0S1tX/KUMah6B10KO > dC3AfI4fJY9dtnF4Pe05ZZjSPhTznHClPc9PS34vD7yvE2K8T0zR5U4JNcMVof47 > zP+SyBwGSr+1CTS4B1SwhpZWGter8uX9z/O9U84CfKF2T1Ci/fPlYO2mv3M/u/e8 > p1MlFLYcnlcl2SGVRwUF2vy7g3e7rN3QRJ85tQGrU+Pmb0BeqXWyWoUQiQ/PD/4w > QaPmKT4KOqGVJ8R6mMVg65JKV5C4zftXIICZHBWhnv0Vs+1jx8rbvaJQ6DcR+CCX > FEbKK0GMuVxhtwJ3TnSIFXF+ZRTViH5zqinaSchXmrPuUc4ZSJxqWlgEYd7WqsG2 > 5lg2KId/RrLJmRGYyRfllBrrHd72YnaAahijXEY+Z2A48TCNA2FmBdRYWFUy0Lpa > P69G9R+2UnjBT9sPRpNzy+P8l0Z5XIz70b0vg9e4UjA+m2s9DHGDBL5KeX78rE6w > yKZE1mc3vormHbBgX8/IlOw/eF3XSsOv4ET8g/GMPXoULqzCcgQbytAtt0pOzzzZ > 6KmLpFcf4eqTTgZVBx+G > =+49l > -END PGP SIGNATURE- > ___ Chicken-users mailing list Chicken-users@nongnu.org http://lists.nongnu.org/mailman/listinfo/chicken-users
