Subject: bug#23949: 25.0.95; Regression in handling error caused by (string-match-p "." nil)

From: Andreas Schwab <[email-masked]>
Date: Wed, 13 Jul 2016 17:03:22 +0200

Eli Zaretskii <[email-masked]> writes:

> Does the following variant of string-match-p look right?  Its intent
> is to limit the effect of inhibit-changing-match-data to the call to
> string-match only, leaving the error handling, if any is needed,
> outside of that binding.
>
> (defsubst string-match-p (regexp string &optional start)
>   "\
> Same as `string-match' except this function does not change the match data."
>   (condition-case err
>       (let ((inhibit-changing-match-data t))
> 	(string-match regexp string start))
>     (error (signal (car err) (cdr err)))))

This optimizes for the rare case that string-match throws an error.
Better would be to bind inhibit-changing-match-data in call_debugger.

Andreas.

-- 
Andreas Schwab, SUSE Labs, [email-masked]
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