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Re: help with pypeg2?

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On Fri, Feb 6, 2015 at 7:55 AM, Neal Becker <ndbecker2@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).

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Re: help with pypeg2? Ian Kelly <ian.g.kelly@gmail.com> - 2015-02-06 09:40 -0700

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