On 07/10/2012 09:14 PM, Philippe Sigaud wrote:
Tue, Jul 10, 2012 at 12:41 PM, Roman D. Boiko<[email protected]> wrote:
One disadvantage of Packrat parsers I mentioned was problematic error
recovery (according to the article from ANTLR website). After some
additional research, I found that it is not a critical problem. To find the
exact place of error (from parser's perspective, not user's) one only needs
to remember the farthest successfully parsed position (among several
backtracking attempts) and the reason that it failed.
IIRC, that's what I encoded in Pegged (admittedly limited) error
reporting: remember the farthest error.
It is also possible to rerun parsing with some additional heuristics after
failing, thus enabling advanced error repair scenarios.
Do people really what error-repairing parsers? I want my parsers to
tell me something is bad, and, optionally to advance a possible
repair, but definitely *not* to automatically repair a inferred error
and continue happily.
FWIW, this is what most HTML parsers are doing.
