On Mon, Nov 27, 2000 at 04:41:34PM -0500, Dan Sugalski wrote:
> Okay, here's a question for those of you with more experience at parsers
> than I have. (Which would be about everyone)
>
> Is there any reasonable case where we would need to backtrack over
> successfully parsed source and redo the parsing? I'm not talking about the
> case where regular expressions run over text and ultimately fail, but
> rather cases where we need to chuck out part of what we have and restart?
Disclaimer: I'm not sure whether you're asking about lexing, tokenizing,
both, or neither.
In current perl, we do something _like_ that to disambiguate certain
situations. Grep the sources for `expectation'. I wouldn't be surprised
if something like this also goes on with, e.g., multi-line regexen.
Oh, you said `reasonable'.
Peace,
* Kurt Starsinic ([EMAIL PROTECTED]) ---------------- Senior Software Architect *
| `It is always possible to aglutenate multiple separate problems |
| into a single complex interdependent solution. In most cases |
| this is a bad idea.' - Ross Callon |