jscheme-user — list for general users

[Jscheme-user] bug in source download instructions

[Jonathan A R. <ja...@mu...>]

I followed the instructions at
http://jscheme.sourceforge.net/jscheme/doc/userman.html@downloadcvs,
and experienced the following:

    jar@rosebud:~$ cvs -d:pserver:ano...@cv...:/cvsroot/jscheme login
    (Logging in to ano...@cv...)
    CVS password: 

    jar@rosebud:~$ cvs -z3:pserver:ano...@cv...:/cvsroot/jscheme co jscheme
    cvs checkout: No CVSROOT specified!  Please use the `-d' option
    cvs [checkout aborted]: or set the CVSROOT environment variable.
    jar@rosebud:~$ 

Not knowing anything about CVS, I then flailed about:

    jar@rosebud:~$ export CVSROOT=/tmp/cvs
    jar@rosebud:~$ mkdir /tmp/cvs
    jar@rosebud:~$ cvs -z3:pserver:ano...@cv...:/cvsroot/jscheme co jscheme
    cvs [checkout aborted]: /tmp/cvs/CVSROOT: No such file or directory
    jar@rosebud:~$ mkdir /tmp/cvs/CVSROOT
    jar@rosebud:~$ cvs -z3:pserver:ano...@cv...:/cvsroot/jscheme co jscheme
    cvs checkout: cannot find module `jscheme' - ignored
    jar@rosebud:~$ 

Can you help?

Thanks
Jonathan
(who is trying to use Jscheme at Millennium Pharmaceuticals for
miscellaneous scripting)

(and by the way, when I tried to run cvs across the company's firewall,
it went south, so I had to do it on my home machine.)

Re: [Jscheme-user] defining new classes

[Timothy H. <tim...@ma...>]

On Monday, January 6, 2003, at 10:00 PM, david may wrote:

> I found this today, and it seems usefull.
> are there any gotchas to this method oc creating
> new class in jscheme?
Thanks for the reference and the nice simple test below!
It certainly looks like a fun domain to play in!
There will be problems with security violations (e.g.
it won't work with unsigned applets and
using Java Web Start you'll have to sign the jars).


>
> Sometimes you want to make a  subclass just to
> override the paint method.
Good point. This has in fact been the only reason we need to
write Java code for Jscheme applications. Have you tried to
use this to create an instance of Panel (or JPanel) that
overrides paint?

>
> the jar file is here..
> http://www.csg.is.titech.ac.jp/~chiba/javassist/
>
> ------------ a simple test -----------
> (import "javassist.*")
> (define  pool  (javassist.ClassPool.getDefault))
> (define cc (.makeClass  pool "Silly"))
> (define m  (CtNewMethod.make
>        "public int silly(int dx) { return 2+dx; }" cc))
> (.addMethod cc m)
>
> (define cloader (Loader. pool))
> (define anewclass  (.loadClass  cloader "Silly"))
> (define ss1 (.newInstance anewclass))
>
> (.silly ss 1)
shouldn't this be
    (.silly ss1 1)


---Tim---

[Jscheme-user] defining new classes

[<da...@da...>]

I found this today, and it seems usefull.
are there any gotchas to this method oc creating 
new class in jscheme?

Sometimes you want to make a  subclass just to 
override the paint method. 

the jar file is here..
http://www.csg.is.titech.ac.jp/~chiba/javassist/

------------ a simple test -----------
(import "javassist.*")
(define  pool  (javassist.ClassPool.getDefault))
(define cc (.makeClass  pool "Silly"))
(define m  (CtNewMethod.make 
       "public int silly(int dx) { return 2+dx; }" cc))
(.addMethod cc m)

(define cloader (Loader. pool))
(define anewclass  (.loadClass  cloader "Silly"))
(define ss1 (.newInstance anewclass))

(.silly ss 1)

Re: [Jscheme-user] Web Start problem

[Ken A. <kan...@bb...>]

I'm now having trouble building JScheme from scratch which may be related to this problem.  Let me play around with this and see if i can get the build fixed by tomorrow.
k
At 02:06 PM 1/1/2003, david may wrote:
>Happy 2003 !
>
>I am have difficulty with makeing my jscheme app work with 
>webstart on windows. It works fine on linux. But on windows
>I get the a security violation.
>
>I probably went about this the wrong way but in order to not have to 
>sign the jscheme jar and jabberbeans jar I created a java class
>and started jscheme in it  like this
>
>    InputPort ip = null;
>    ip = Scheme.openResource("init.scm");
>    if (ip == null)  E.warn("(load) can't open the silly init.scm");
>    else Scheme.load(ip);
>
>I put this and my init.scm in a jar and signed it.
>and made the other jars extensions
>
><extension name="jabberbeans"
>   href="jabberbeans.jnlp">
></extension>
><extension name="jscheme"
>   href="jscheme.jnlp">
></extension>
>
>and  then 
>set 
> <all-permissions/> 
>
>This all works on linux but on windows 2000 it fails.
>
>
>Java Web Start 1.2 Console, started Wed Jan 01 10:51:34 PST 2003
>Java 2 Runtime Environment: Version 1.4.1_01 by Sun Microsystems Inc.
>In openResource(init.scm):
>java.lang.ExceptionInInitializerError
>        at jsint.Scheme.openResource(Scheme.java:197)
>        at JwsJscheme.<init>(JwsJscheme.java:8)
>        at JwsJscheme.main(JwsJscheme.java:13)
>        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
>        at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
>        at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
>        at java.lang.reflect.Method.invoke(Unknown Source)
>        at com.sun.javaws.Launcher.executeApplication(Unknown Source)
>        at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
>        at com.sun.javaws.Launcher.continueLaunch(Unknown Source)
>        at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
>        at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
>        at com.sun.javaws.Launcher.run(Unknown Source)
>        at java.lang.Thread.run(Unknown Source)
>Caused by: java.security.AccessControlException: access denied (java.lang.RuntimePermission setContextClassLoader)
>        at java.security.AccessControlContext.checkPermission(Unknown Source)
>        at java.security.AccessController.checkPermission(Unknown Source)
>        at java.lang.SecurityManager.checkPermission(Unknown Source)
>        at java.lang.Thread.setContextClassLoader(Unknown Source)
>        at jsint.Import.<clinit>(Import.java:48)
>        ... 14 more
>** WARNING: (load) can't open the silly init.scm
>
>
>thanks,
>davud
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by:ThinkGeek
>Welcome to geek heaven.
>http://thinkgeek.com/sf
>_______________________________________________
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>https://lists.sourceforge.net/lists/listinfo/jscheme-user

Re: [Jscheme-user] bug in string->number

[Ken A. <kan...@bb...>]

At 03:39 PM 1/2/2003, Timothy Hickey wrote:

>On Monday, December 30, 2002, at 02:45 PM, Ken Anderson wrote:
>
>>Tim,
>>
>>I think i should refactor the stringToNumber code to determine the type and size of the number and then attempt an appropriate conversion.  
>>readWholeNumber seems more complicated than it needs to be, for example it treats negative numbers specially were you trying to get around some limitation?
>Refactoring is always a good idea if it makes to code cleaner, and in this case it probably will.
>>
>>Unfortunately, I've noticed that Integer.parseInt throws a numeric exception for numbers such as 0xDadaCafe 0x80000000 02000000000, while our current code returns a Long.  Long.parseLong has a similar problem.  So, the best thing might be to use Long.parseLong and then .intValue to get an Integer.
>>I presume this has to do with numbers being signed,
>We may want to make it easier for people to switch from Java syntax to R4RS syntax for contants (longs, etc.)
>In this particular case, "01438" is not a valid Java number and so should probably throw and exception

Yes, it did but we just returned a float. I'll fix this.

>when usingJavaSyntax  but should return the integer 1438 when using Scheme lexical syntax.
>
>---Tim---
>
>>
>>
>>At 10:48 AM 12/30/2002, Jonathan A Rees wrote:
>>>I believe the following behavior is incorrect (according to the scheme
>>>report).
>>>
>>>   Jscheme 5.0 04/05/2002 http://jscheme.sourceforge.net
>>>>(string->number "01438")
>>>   1438.0
>>>
>>>It should be more like the following:
>>>
>>>>(string->number "1438")
>>>   1438
>>>
>>>Jonathan
>>>
>>>
>>>-------------------------------------------------------
>>>This sf.net email is sponsored by:ThinkGeek
>>>Welcome to geek heaven.
>>>http://thinkgeek.com/sf
>>>_______________________________________________
>>>Jscheme-user mailing list
>>>Jsc...@li...
>>>https://lists.sourceforge.net/lists/listinfo/jscheme-user

Re: [Jscheme-user] bug in string->number

[Timothy H. <tim...@ma...>]

On Monday, December 30, 2002, at 02:45 PM, Ken Anderson wrote:

> Tim,
>
> I think i should refactor the stringToNumber code to determine the type 
> and size of the number and then attempt an appropriate conversion.  
> readWholeNumber seems more complicated than it needs to be, for example 
> it treats negative numbers specially were you trying to get around some 
> limitation?
Refactoring is always a good idea if it makes to code cleaner, and in 
this case it probably will.
>
> Unfortunately, I've noticed that Integer.parseInt throws a numeric 
> exception for numbers such as 0xDadaCafe 0x80000000 02000000000, while 
> our current code returns a Long.  Long.parseLong has a similar 
> problem.  So, the best thing might be to use Long.parseLong and then 
> .intValue to get an Integer.
> I presume this has to do with numbers being signed,
We may want to make it easier for people to switch from Java syntax to 
R4RS syntax for contants (longs, etc.)
In this particular case, "01438" is not a valid Java number and so 
should probably throw and exception
when usingJavaSyntax  but should return the integer 1438 when using 
Scheme lexical syntax.

---Tim---

>
>
> At 10:48 AM 12/30/2002, Jonathan A Rees wrote:
>> I believe the following behavior is incorrect (according to the scheme
>> report).
>>
>>    Jscheme 5.0 04/05/2002 http://jscheme.sourceforge.net
>>> (string->number "01438")
>>    1438.0
>>>
>>
>> It should be more like the following:
>>
>>> (string->number "1438")
>>    1438
>>>
>>
>> Jonathan
>>
>>
>> -------------------------------------------------------
>> This sf.net email is sponsored by:ThinkGeek
>> Welcome to geek heaven.
>> http://thinkgeek.com/sf
>> _______________________________________________
>> Jscheme-user mailing list
>> Jsc...@li...
>> https://lists.sourceforge.net/lists/listinfo/jscheme-user
>

Re: [Jscheme-user] Web Start problem

[Timothy H. <tim...@ma...>]

On Wednesday, January 1, 2003, at 02:06 PM, david may wrote:

> Happy 2003 !
>
> I am have difficulty with makeing my jscheme app work with
> webstart on windows. It works fine on linux. But on windows
> I get the a security violation.
>
> I probably went about this the wrong way but in order to not have to
> sign the jscheme jar and jabberbeans jar
Are you running the lastest Jscheme built from CVS. It sounds like
this might be a problem with the class loader extensions that we've
built into Jscheme in the past few months, but I think they were
resolved recently.....

I think the two calls to setContextClassLoader in the file 
jsint/Import.java
should be enclosed in a tryCatch.....

---Tim---

>  I created a java class
> and started jscheme in it  like this
>
>     InputPort ip = null;
>     ip = Scheme.openResource("init.scm");
>     if (ip == null)  E.warn("(load) can't open the silly init.scm");
>     else Scheme.load(ip);
>
> I put this and my init.scm in a jar and signed it.
> and made the other jars extensions
>
> <extension name="jabberbeans"
>    href="jabberbeans.jnlp">
> </extension>
> <extension name="jscheme"
>    href="jscheme.jnlp">
> </extension>
>
> and  then
> set
>  <all-permissions/>
>
> This all works on linux but on windows 2000 it fails.
>
>
> Java Web Start 1.2 Console, started Wed Jan 01 10:51:34 PST 2003
> Java 2 Runtime Environment: Version 1.4.1_01 by Sun Microsystems Inc.
> In openResource(init.scm):
> java.lang.ExceptionInInitializerError
> 	at jsint.Scheme.openResource(Scheme.java:197)
> 	at JwsJscheme.<init>(JwsJscheme.java:8)
> 	at JwsJscheme.main(JwsJscheme.java:13)
> 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
> 	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
> 	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
> 	at java.lang.reflect.Method.invoke(Unknown Source)
> 	at com.sun.javaws.Launcher.executeApplication(Unknown Source)
> 	at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
> 	at com.sun.javaws.Launcher.continueLaunch(Unknown Source)
> 	at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
> 	at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
> 	at com.sun.javaws.Launcher.run(Unknown Source)
> 	at java.lang.Thread.run(Unknown Source)
> Caused by: java.security.AccessControlException: access denied 
> (java.lang.RuntimePermission setContextClassLoader)
> 	at java.security.AccessControlContext.checkPermission(Unknown Source)
> 	at java.security.AccessController.checkPermission(Unknown Source)
> 	at java.lang.SecurityManager.checkPermission(Unknown Source)
> 	at java.lang.Thread.setContextClassLoader(Unknown Source)
> 	at jsint.Import.<clinit>(Import.java:48)
> 	... 14 more
> ** WARNING: (load) can't open the silly init.scm
>
>
> thanks,
> davud
>
>
> -------------------------------------------------------
> This sf.net email is sponsored by:ThinkGeek
> Welcome to geek heaven.
> http://thinkgeek.com/sf
> _______________________________________________
> Jscheme-user mailing list
> Jsc...@li...
> https://lists.sourceforge.net/lists/listinfo/jscheme-user
>

[Jscheme-user] Web start problem

[<da...@da...>]

I discovered my java Policies on my linux box were set to all permissions.
Apparently I did this and forgot. Anyhow I fixed that and 
jscheme apps fail on linux as well with the same security problem.

[Jscheme-user] Web Start problem

[<da...@da...>]

Happy 2003 !

I am have difficulty with makeing my jscheme app work with 
webstart on windows. It works fine on linux. But on windows
I get the a security violation.

I probably went about this the wrong way but in order to not have to 
sign the jscheme jar and jabberbeans jar I created a java class
and started jscheme in it  like this

    InputPort ip = null;
    ip = Scheme.openResource("init.scm");
    if (ip == null)  E.warn("(load) can't open the silly init.scm");
    else Scheme.load(ip);

I put this and my init.scm in a jar and signed it.
and made the other jars extensions

<extension name="jabberbeans"
   href="jabberbeans.jnlp">
</extension>
<extension name="jscheme"
   href="jscheme.jnlp">
</extension>

and  then 
set 
 <all-permissions/> 

This all works on linux but on windows 2000 it fails.


Java Web Start 1.2 Console, started Wed Jan 01 10:51:34 PST 2003
Java 2 Runtime Environment: Version 1.4.1_01 by Sun Microsystems Inc.
In openResource(init.scm):
java.lang.ExceptionInInitializerError
	at jsint.Scheme.openResource(Scheme.java:197)
	at JwsJscheme.<init>(JwsJscheme.java:8)
	at JwsJscheme.main(JwsJscheme.java:13)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at com.sun.javaws.Launcher.executeApplication(Unknown Source)
	at com.sun.javaws.Launcher.executeMainClass(Unknown Source)
	at com.sun.javaws.Launcher.continueLaunch(Unknown Source)
	at com.sun.javaws.Launcher.handleApplicationDesc(Unknown Source)
	at com.sun.javaws.Launcher.handleLaunchFile(Unknown Source)
	at com.sun.javaws.Launcher.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)
Caused by: java.security.AccessControlException: access denied (java.lang.RuntimePermission setContextClassLoader)
	at java.security.AccessControlContext.checkPermission(Unknown Source)
	at java.security.AccessController.checkPermission(Unknown Source)
	at java.lang.SecurityManager.checkPermission(Unknown Source)
	at java.lang.Thread.setContextClassLoader(Unknown Source)
	at jsint.Import.<clinit>(Import.java:48)
	... 14 more
** WARNING: (load) can't open the silly init.scm


thanks,
davud

Re: [Jscheme-user] bug in string->number

[Ken A. <kan...@bb...>]

Tim,

I think i should refactor the stringToNumber code to determine the type and size of the number and then attempt an appropriate conversion.  readWholeNumber seems more complicated than it needs to be, for example it treats negative numbers specially were you trying to get around some limitation?

Unfortunately, I've noticed that Integer.parseInt throws a numeric exception for numbers such as 0xDadaCafe 0x80000000 02000000000, while our current code returns a Long.  Long.parseLong has a similar problem.  So, the best thing might be to use Long.parseLong and then .intValue to get an Integer.
I presume this has to do with numbers being signed, 


At 10:48 AM 12/30/2002, Jonathan A Rees wrote:
>I believe the following behavior is incorrect (according to the scheme
>report).
>
>    Jscheme 5.0 04/05/2002 http://jscheme.sourceforge.net
>    > (string->number "01438")
>    1438.0
>    > 
>
>It should be more like the following:
>
>    > (string->number "1438")
>    1438
>    > 
>
>Jonathan
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by:ThinkGeek
>Welcome to geek heaven.
>http://thinkgeek.com/sf
>_______________________________________________
>Jscheme-user mailing list
>Jsc...@li...
>https://lists.sourceforge.net/lists/listinfo/jscheme-user

Re: [Jscheme-user] bug in string->number

[Ken A. <kan...@bb...>]

Hi Johathan,

What's happening here is that one of the JScheme extensions is to allow the use of Java syntax for numbers.  You can turn it off with:
> (set! U.useJavaSyntax$ #f)
#t
> (string->number "01438")
1438

Because of the leading "0" JScheme attempts to read the string in octal.
Because of the "8" an exception is thrown.  Our code catches the exception and simply tries to read the string as a float, which succeeds.  Clearly it should throw an error, which might have at least given you a hint.  I'll work to Tim to clean this up, thanks.

k
At 10:48 AM 12/30/2002, Jonathan A Rees wrote:
>I believe the following behavior is incorrect (according to the scheme
>report).
>
>    Jscheme 5.0 04/05/2002 http://jscheme.sourceforge.net
>    > (string->number "01438")
>    1438.0
>    > 
>
>It should be more like the following:
>
>    > (string->number "1438")
>    1438
>    > 
>
>Jonathan
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by:ThinkGeek
>Welcome to geek heaven.
>http://thinkgeek.com/sf
>_______________________________________________
>Jscheme-user mailing list
>Jsc...@li...
>https://lists.sourceforge.net/lists/listinfo/jscheme-user

[Jscheme-user] bug in string->number

[Jonathan A R. <ja...@mu...>]

I believe the following behavior is incorrect (according to the scheme
report).

    Jscheme 5.0 04/05/2002 http://jscheme.sourceforge.net
    > (string->number "01438")
    1438.0
    > 

It should be more like the following:

    > (string->number "1438")
    1438
    > 

Jonathan

[Jscheme-user] overriding paint method with jscheme

[<da...@da...>]

I am back at it again..
JScheme is a great way to explore the endless Java APIS.
I just  got some jscheme to play mp3s as well as transform
XML, and load the DOM from a database.. 
So now I am trying figure out the simples way to 
display some images. It appears the normal java method
is to override the paint() method. I looked at jlib but
it did not mention images. What would be  cool is to include
some visual presenatations  with the mp3s in a jar. 
Animation in jscheme??

[Jscheme-user] Re: easy way to break list up?

[Ken A. <kan...@bb...>]

Yes,
In elf/sort.scm there is (by n xs):

(define (by n xs)
  (define (by0 i xs items so-far)
    (if (= i 0) (by0 n xs '() (cons (reverse items) so-far))
        (if (null? xs) (finish items so-far)
            (by0 (- i 1) (cdr xs) (cons (car xs) items) so-far))))
  (define (finish items so-far)
    (reverse
     (if (null? items) so-far
         (cons (reverse items) so-far))))
  (assert (> n 0))
  (by0 n xs '() '()))

I think i got this idea from Peter Norvig:
Put parens around your data any way it comes and use (by) and (map) to
organize it into the way you want it.

k

At 05:36 PM 11/7/2002, Renu Kurien Bostwick wrote:

>Ken - 
>
>Do you know of an easy way (jscheme function perhaps) that'll break up
>a list into sublists that are max of n long?
>
>'(a b c d e f g h i j) with n=3 would become
>
>'((a b c) (d e f) (g h i) (j)) 
>
>or 
>
>'((a) (b c d) (e f g) (h i j))
>
>The ordering isn't important to me.  I've been writing my own function
>to do the split but it involves converting to vectors and back to
>lists.  Is there a more elegant solution?
>
>Thanks,
>Renu
>
>-- 
>-----------------------
>Renu Kurien Bostwick
>re...@bb...
>(617) 873-4543
>-----------------------

Re: [Jscheme-user] xml

[Ken A. <kan...@bb...>]

I think i gave you some suggestions.
What seems to be working so far?

At 05:29 PM 10/23/2002, david may wrote:
>I am trying to learn how to user XML apis in Java 1.4
>using jscheme. What is the best way to deal with handlers.
>I have been looking at the Proxy example in the jscheme src
>but i am wondering if  I might be better off writting a java handler.
>thanks,
>davud
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by: Influence the future 
>of Java(TM) technology. Join the Java Community 
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[Jscheme-user] A plan for Spam

[Ken A. <kan...@bb...>]

I implemented Paul Graham's spam filter:
http://www.paulgraham.com/spam.html.

I'm impressed at how simple (< 160 lines) and effective it is.

For training i used 290 spams and the first 500 messages in my inbox (which includes spam, though only 2 in the first 500.

I then ran it on the 3200 messages in my inbox and it found 313 spams.
There was one border line false positive - a Java Development bulk mailing.
Not bad for 2 - 3 hours work!

The code is Eudora specific, but you should be able to tailor it to your mail reader easily.  It can classify about 10 emails/sec on my machine, which is plenty fast enough for playing around.

Thanks, Paul!

k 

Re: [Jscheme-user] xml

[Ken A. <kan...@bb...>]

See src/dclass/SaxHandler.scm and SaxExp.scm
These compile into elf/SaxHandler.java and elf/SaxExp.java

SaxHandler reads an xml file and prints its components.
SaxExp reads and xml file and returns an s-expression.  I think i have a slightly newer version.

k

At 06:29 PM 10/23/2002, david may wrote:
>I am trying to learn how to user XML apis in Java 1.4
>using jscheme. What is the best way to deal with handlers.
>I have been looking at the Proxy example in the jscheme src
>but i am wondering if  I might be better off writting a java handler.
>thanks,
>davud
>
>
>-------------------------------------------------------
>This sf.net email is sponsored by: Influence the future 
>of Java(TM) technology. Join the Java Community 
>Process(SM) (JCP(SM)) program now. 
>http://ads.sourceforge.net/cgi-bin/redirect.pl?sunm0002en
>
>_______________________________________________
>Jscheme-user mailing list
>Jsc...@li...
>https://lists.sourceforge.net/lists/listinfo/jscheme-user

[Jscheme-user] xml

[<da...@da...>]

I am trying to learn how to user XML apis in Java 1.4
using jscheme. What is the best way to deal with handlers.
I have been looking at the Proxy example in the jscheme src
but i am wondering if  I might be better off writting a java handler.
thanks,
davud

[Jscheme-user] Re: elegant scheme for list to string?

[Ken A. <kan...@bb...>]

Using {} flattens any lists and string appends the results.  So, when you really want the lisp value as a string, use .toString or something.


> (define data '((tokenizer.scm 1.49) (match.scm 1.47)))
((tokenizer.scm 1.49) (match.scm 1.47))
> {[data]}
"tokenizer.scm1.49match.scm1.47"
> (.toString data)
"((tokenizer.scm 1.49) (match.scm 1.47))"
> 

At 06:34 PM 10/21/2002, you wrote:

>Ken -
>
>What's the simplest way in Scheme to go from a list like 
>
>'((tokenizer.scm 1.49) (match.scm 1.47))
>
>to a string like
>
>"((tokenizer.scm 1.49) (match.scm 1.47))"
>
>I thought I might be able to use the {} but it strips parens and
>spaces:
>
>> cvsTokenizerTags
>((tokenizer.scm 1.49) (match.scm 1.47))
>> {[cvsTokenizerTags]}
>"tokenizer.scm1.49match.scm1.47"
>
>Do you know of an elegant way for me to get a string representation of
>the list?
>
>Thanks,
>Renu
>
>-- 
>-----------------------
>Renu Kurien Bostwick
>re...@bb...
>(617) 873-4543
>-----------------------

[Jscheme-user] ignoreable newline in quasi-string

[Ken A. <kan...@bb...>]

Rusty has been using quasi-string syntax to generate regular expression from subparts.  These expressions get pretty long (my mailer insists on folding):

(define lon {((\\d\\d(\\d)*([numSplit]\\d+)??[lonDir])|([lonDir]\\d(\\d)?(\\d)? ?(DEG)?\\d(\\d)?([decimal])? ?[minutePat]?[secPat]?))})

It would be nice to have a way to ignore a newline.  A clever way Rusty came up with is to use []:

> {hello[
   ] there}
"hello there"

[Jscheme-user] MzScheme Module/Macro paper

[Derek U. <Der...@on...>]

A few weeks back there was some discussion on bugs in the way macros
interacted with compilation.  Matthew Flatt has a paper that talks about the
MzScheme system for solving the problem:

http://www.cs.utah.edu/plt/publications/macromod.pdf

(via Lambda the Ultimate).

Derek

--
Derek Upham
Senior Software Engineer
Ontain
1750 112th Ave NE, Suite C-245
Bellevue, WA 98004-3727
Tel: 425-460-1886
der...@on...

Re: [Jscheme-user] bug in compiled (or)

[Timothy H. <tim...@ma...>]

On Tuesday, September 10, 2002, at 08:11 PM, Graham Spencer wrote:
> Given this file:
>
>   ;; or.scm
>   (define (test-or) (or #f 1 2))
>
> If I compile or.scm to a .class file, I get this behavior from 
> jscheme.REPL:
>
>   > (or.load)
>   #null
>   > (test-or)
>   #t
Whoops!

You are exactly right. This is the wrong behavior. It has been corrected 
in the latest version of jscheme
(download from CVS) which is Jscheme 5.1.2 (9/11/2002)

Thanks for the bug report!

---Tim---

P.S.
We're still thinking over the compiler/macros issues....
I think the idea of compiling "(load ...)" so that it scans for macros
is probably a good idea.... Something similar would need to be
done for (prog.load)


>   > (load "or.scm")
>   #t
>   > (test-or)
>   1
>
> I think the (load "or.scm") behavior is correct -- (or) should return 
> the first true value, not #t. Is that right? Thanks,
>
> --g
>
>
>
> -------------------------------------------------------
> In remembrance
> www.osdn.com/911/
> _______________________________________________
> Jscheme-user mailing list
> Jsc...@li...
> https://lists.sourceforge.net/lists/listinfo/jscheme-user
>

[Jscheme-user] bug in compiled (or)

[Graham S. <fo...@pa...>]

Given this file:

   ;; or.scm
   (define (test-or) (or #f 1 2))

If I compile or.scm to a .class file, I get this behavior from jscheme.REPL:

   > (or.load)
   #null
   > (test-or)
   #t
   > (load "or.scm")
   #t
   > (test-or)
   1

I think the (load "or.scm") behavior is correct -- (or) should return 
the first true value, not #t. Is that right? Thanks,

--g

Re: [Jscheme-user] Ability to Sub-class a Java Object?

[Ken A. <kan...@bb...>]

If you need to make inner classes with behavior specialized with scheme,
do it by writing a wrapper class that takes the scheme behavior you want in 
the constructor.  Here's your example:

(define-class
   (package foo)
   (public class MyFoo)

   (private Procedure action)

   (public MyFoo (Procedure action) (.action$# this action))

   (public void bar () ((.action$# this)))
   )

Here's a sample use:
 > (.bar (foo.MyFoo. (lambda () (print 'hi))))
hi
#null
 >

At 01:17 PM 9/9/2002, Kyle R . Burton wrote:
> > There are several ways to do this.  see
> > http://jscheme.sourceforge.net/jscheme/src/dclass/dclass.html
> >
> > The closest thing to what Jython does is
> > (define-class).  This requires you to declare types for all your methods,
> > so it isn't as nice as Jython's way.
> >
> > I'd like to do it Jython's way at some point.
>
>Thanks for the quick reply.  I have been able to create a Scheme class that
>sub-classes a Java class.
>
>I do have another question though.  Is it possible to create anonymous clases?
>Java supports a syntax for declaring anonymous classes:
>
>   Foo foo = new Foo() {
>     public void bar () {
>       System.out.println("in bar()");
>     }
>   };
>
>Is there a corresponding construct in JScheme?
>
>
>Thank you,
>Kyle R. Burton
>
>--
>
>------------------------------------------------------------------------------
>Wisdom and Compassion are inseparable.
>         -- Christmas Humphreys
>mo...@vo...                            http://www.voicenet.com/~mortis
>------------------------------------------------------------------------------
>
>
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Re: [Jscheme-user] Ability to Sub-class a Java Object?

[Kyle R . B. <mo...@vo...>]

> There are several ways to do this.  see
> http://jscheme.sourceforge.net/jscheme/src/dclass/dclass.html
> 
> The closest thing to what Jython does is
> (define-class).  This requires you to declare types for all your methods, 
> so it isn't as nice as Jython's way.
> 
> I'd like to do it Jython's way at some point.

Thanks for the quick reply.  I have been able to create a Scheme class that
sub-classes a Java class.

I do have another question though.  Is it possible to create anonymous clases?
Java supports a syntax for declaring anonymous classes:

  Foo foo = new Foo() {
    public void bar () {
      System.out.println("in bar()");
    }
  };

Is there a corresponding construct in JScheme?


Thank you,
Kyle R. Burton

-- 

------------------------------------------------------------------------------
Wisdom and Compassion are inseparable.
        -- Christmas Humphreys
mo...@vo...                            http://www.voicenet.com/~mortis
------------------------------------------------------------------------------