Ian Kelly wrote: > On Fri, Feb 6, 2015 at 7:55 AM, Neal Becker <ndbeck...@gmail.com> wrote: >> Trying out pypeg2. The below grammar is recursive. A 'Gen' is an ident >> followed by parenthesized args. args is a csl of alphanum or Gen. >> >> The tests 'p' and 'p2' are fine, but 'p3' fails >> SyntaxError: expecting u')' >> >> >> from __future__ import unicode_literals, print_function >> from pypeg2 import * >> >> ident = re.compile (r'[a-z]+') >> alphanum = re.compile (r'[a-z0-9]+') >> num = re.compile (r'[0-9]+') >> >> class args (List): >> grammar = maybe_some ( csl ([alphanum, Gen])) > > I'm not familiar with pypeg2, but should this use optional instead of > maybe_some? The csl function already produces a list, so the result of > maybe_some on that would be one or more consecutive lists. > > Also, it looks from the docs like it should just be "csi(alphanum, > Gen)" (no list in the arguments).
It didn't work without [list..] (even trivial examples did not work without it). I don't know if it's broken, I though csl (*args) should mean a comma-sep-list of _any_ of the *args, but it doesn't work. [list] means alternatives, and does seem to work (for simple examples). -- -- Those who don't understand recursion are doomed to repeat it -- https://mail.python.org/mailman/listinfo/python-list
