[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: `match-data' set improperly
From: |
Kim F. Storm |
Subject: |
Re: `match-data' set improperly |
Date: |
12 Feb 2003 11:53:24 +0100 |
User-agent: |
Gnus/5.09 (Gnus v5.9.0) Emacs/21.3.50 |
Matthew Swift <swift@alum.mit.edu> writes:
> Evaluating the following `let' form gives varying results, but the results
> should be consistent. Correct results are always returned when `s' is "The
> quick fox...", which matches the regexp `r'. When `s' is "great grey
> green...", which does not match `r', the results in my trials have never been
> correct: either an 'args-out-of-range' error is raised, or incorrect data is
> given, which appears to be the result of applying match-data from matching a
> previous value of `s' ("The quick fox...") to the current value of `s'.
> Sample
> results are copied below.
>
> My *guess* is that when `string-match' fails, it either fails to set
> `match-data' or sets it incorrectly in one of two (or more) ways.
My guess is that you are not supposed to use match-data when
string-match fails, so its value is indeed undefined in that case.
What _valid_ values would you expect it to contain after the match failed?
--
Kim F. Storm http://www.cua.dk