Regex: Parsing Lisp with Python

Thomas Guettler zopestoller at thomas-guettler.de
Thu Aug 8 16:22:38 CEST 2002


Yigal Duppen wrote:

>>I need to parse lisp with python. Has anyone
>>experience with this?
>>
> 
> Yes I do :)
> Actually, I have a program that parses Scheme, but as far as the syntax is 
> concerned, that's probably OK.
> 
> I used Plex for it -- much better than regular expressions for non-trivial 
> tokens.


Thank you for your quick reply.

I tried it like this, but this gives me all tokens
serialized. It is hard to get the second symbol without
counting all open and close tokens. Is there a way to get
the tokens in nested lists?

((a b) c) --> [[a b] c]

I tried it like this:

import lexer

fd=open(sys.argv[1])
while 1:
     line=fd.readline()
     if not line:
         break
     tokens=lexer.tokenize(line)
     print tokens

  thomas





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