Dolphin port of Squeak's Url classes

Hi,

        Is there any port of Squeak's url classes?  If not, I already
filed it out from Squeak, but how do I import it into Dolphin? O:-)

Thanks

Fernando
>
> Is there any port of Squeak's url classes?

Nobody has answered yet, so probably not.

>If not, I already
> filed it out from Squeak, but how do I import it into Dolphin? O:-)

Basically, four stages:
a. Transform the filed out .st files so Dolphin can accept them - this is
pretty easy.
b. File in the transformed files - and probably get a shower of complaints
in the Transcript about syntax errors.
c. Modify the filed in code to remove the errors - this can be tedious, and
represents most of the work.
d. Test and verify that the methods work in Dolphin as in Squeak.

For stage a., the main change needed is to translate the Squeak assignment
operator (which appears as a left arrow in Squeak listings, but is an
underscore when listed in Dolphin) into the Smalltalk standard :=  There may
also be a problem with line terminator conventions - I have done this, but I
can't remember whether Dolphin will accept the Squeak convention. This stage
can be done manually with the editing facilities of the Dolphin workspace,
or it only needs a trivial bit of code in a workspace to read in a file,
make the changes and output the transformed code.

Stage b. can be done in any of the Dolphin system tools - the Class Browser
is probably the obvious one.

Stage c. is the real fun. There are a few differences between Squeak and
Dolphin syntax which turn up frequently. The one I found most often is with
the #ifNotNil: message. In Squeak, the argument to this is a zero-argument
block, while for Dolphin the block has to have one argument. It does not
matter what argument you insert here, since by definition the code in the
block does not refer to it. There is also a Squeak array-constructor using
braces {}, which does not occur in Dolphin; usually this can become Array
with: with: . . . . .  Some of these differences could no doubt be removed
in the editing in stage a.

One issue you may come up against is how much of the Squeak system you want
to import. I have not looked at all the Url classes, but if they refer to
other parts of the Network categories you will have to decide whether to
import those also or to replace the references with references to the
Dolphin equivalent, where it exists. These projects can spread!

Good luck

Peter Kenny

Peter, Fernando

> There
> may also be a problem with line terminator conventions - I have done
> this, but I can't remember whether Dolphin will accept the Squeak
> convention.

It's as well to convert the .st (or whatever) files to Window's line-ending
conventions before loading them into Dolphin.  I don't know what Squeak uses
either, but it if's the Unix convention, then what happens is that Dolphin
parses and compiles the code just fine, and it all looks OK in the browsers.
It's only when you do something that depends on the IP maps (generated by the
compiler to help the debugger) that you hit problems.  Then you will find that
the debugger doesn't display the currently executing expression correctly, and
other tools (such as Ian's profiler) are also adversely affected.

    -- chris

Fernando

"Chris Uppal" <[hidden email]> wrote...
> Peter, Fernando
>
> > There
> > may also be a problem with line terminator conventions - I have done
> > this, but I can't remember whether Dolphin will accept the Squeak
> > convention.
>
> It's as well to convert the .st (or whatever) files to Window's
line-ending
> conventions before loading them into Dolphin.  I don't know what Squeak
uses

Chris is quite right. I have looked back at the code I used to feed Squeak
file-outs into Dolphin. In fact the Squeak convention is to use carriage
return alone as the line terminator (though looking at my code it seems as
though I found some cr-lf combinations as well). The following code
fragment, executed in a workspace, is what I used to convert the Squeak
Html-Parser code for Dolphin; just change the file name in the first line
for your case. The converted file has the name of the input file with an
added 1 at the end. All left-arrow assignments are changed to := and any
occurrences of cr not followed by lf have the lf inserted.

fileName := 'c:\Documents and Settings\Peter\My
Documents\Squeak\Html-Parser'.
str := FileStream read: fileName,'.st'.
out := FileStream open: fileName,'1.st' mode: #create.
[str atEnd] whileFalse:
 [ch := str next.
 ch = $_ ifTrue: [out nextPutAll: ':=']
  ifFalse: [out nextPut: ch.
    (ch = 13 asCharacter ) ifTrue:
     [str peekFor: 10 asCharacter.
     out nextPut: 10 asCharacter]]].
str close.
out close.

It may not be elegant, but I have tested it and it works. Hope this helps.

Peter Kenny

On Wed, 25 May 2005 00:59:51 +0100, "Peter Kenny"
<[hidden email]> wrote:


[snip]
>
>It may not be elegant, but I have tested it and it works. Hope this helps.

I just wrote a python script to do the conversion, and it seems to
work fine:

----------
# -*- coding: latin1 -*-

"""
Wed May 25, 2005 14:06
Converts Squeak fileouts to a format Dolphin can understand:
- Convert linefeeds from unix to windows
- Convert _ into :=
- Convert the #ifNotNil: message (niladic in Squeak and monadic in
Dolphin)
"""
from __future__ import nested_scopes
import sys, re, os.path, string

def usage():
    print "Usage\n\tunSqueak file_name"
    print __doc__
   
def convert():

    def lineFeeds(inp):
        lines = inp.splitlines()
        inp = string.join(lines, '\r\n')
        return inp
   
    def assignment(inp):
        p = re.compile('_', re.IGNORECASE)
        inp = p.sub(':=', inp)
        return inp

    def ifNotNil(inp):
        p = re.compile(r'(ifNotNil:\s*\[)')
        inp = p.sub(r'\g<1> :dummy | ', inp)
        return inp
   
    txt = open(sys.argv[1]).read()

    txt = lineFeeds(assignment(ifNotNil(txt)))
   
    path = os.path.splitext(sys.argv[1])
    of = open(path[0] + '_dolphin' + path[1],'wb')
    of.write(txt)
    of.close()
    print 'File %s successfuly converted'%(path[0] + '_dolphin' +
path[1])
   
# 'main'
if __name__ == "__main__":
    if len(sys.argv) < 2 or len(sys.argv) > 2:
        usage()
    else:
        convert()
-----------------------

Maybe I should have written it in St...

"Fernando Rodriguez" wrote ...

> I just wrote a python script to do the conversion, and it seems to
> work fine:
[snip]
> Maybe I should have written it in St...

Fernando

Two quick points:
a. My code does not modify the #ifNotNil: syntax; if it did, I would have to
use something more complicated than the simple character-by-character
processing, and no doubt this would look messier than your regex approach.
b. The comment in your script implies that the Squeak line terminator uses
the Unix convention, but this AFAIK is not so. Unix uses lf only as line
terminator, while Squeak uses cr only. If your python script works OK it can
clearly cope with the Squeak convention, while for example Dolphin
SequencedStream>>nextLine would not.

Peter