On Fri, 8 Apr 2005, Carsten Haese wrote: > On Thu, 2005-04-07 at 14:51, Åsmund Grammeltvedt wrote: > > Hi. > > > > I am trying to implement a small compiler in python and, trying to use > > something a bit more pythonic than lex/yacc, ended up with ply > > (http://systems.cs.uchicago.edu/ply/). The only problem is that whereas > > yacc accepts the grammar and appears to parse it correctly, ply does not.
> Maybe this is a PLY bug? LALR(1) support appears to be a relatively > recent addition to PLY. Have you tried contacting PLY's author? > > For what it's worth, it appears that you can make your example grammar > work in LALR-mode PLY by eliminating the empty production and making the > Block rule right recursive like this: > Of course, I don't know whether this rewrite is applicable to your > larger grammar. Unfortunately, it is not. Fortunately, I tried PyBison as a replacement and everything worked perfectly. So I suspect, as you said, that this is a bug with PLY's LALR(1) implementation. Thanks for the help. -- Åsmund Grammeltvedt Are you infringing, citizen? | webshop.ffii.org/ -- http://mail.python.org/mailman/listinfo/python-list
