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- Subject: Re: lpeg could infer the validity of this grammar.
- From: Dirk Laurie <dirk.laurie@...>
- Date: Sun, 14 Dec 2014 22:56:20 +0200
2014-12-14 21:39 GMT+02:00 Sam Putman <atmanistan@gmail.com>:
> expr = token + ( V"group" + V"factor" + V"term")
-- semicolon needed here
> group = P"(" * V"expr"^0 * P")";
> factor = #token * V"expr" * (P"*" + P"/") * V"expr";
> This program fails with "rule 'expr' may be left recursive".
If `expr` is not `token` or `group`, it tries `factor`.
The rule for `factor` invokes V"expr" before any
input has been consumed.
