Basic regex question

chaitins_omega has asked for the wisdom of the Perl Monks concerning the following question:

Hi, I have a basic question on regexes. Consider the following regex:

/^$string/;
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How can I tell Perl not to interpret meta-characters in $string such that I could say, for example:

$string = "\$foo";
/^$string/;
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... and have the effect be that $_ is left-anchor searched for the uninterpolated text literal "$foo"? Thanks.

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Re: Basic regex question by runrig (Abbot) on Jul 18, 2007 at 19:26 UTC
quotemeta (from perlfunc) or `\Q` (from perlre) (they are the same thing just used in different places): `$string = quotemeta('$foo'); /^$string/; # Or $string = '$foo'; /\Q$string/;` [download]	[reply] [d/l] [select]
Re: Basic regex question by FunkyMonk (Bishop) on Jul 18, 2007 at 19:27 UTC
You can either use the `\Q...\E` construct (documented in perlre) within a regex, or the quotemeta function call. `#\E not necessary at end of pattern /^\Q$string/ and print "A match!\n"; #or, same thing $string=quotemeta $string; /^$string/ and print "A match!\n";` [download] update: Re-slanted my slashes. Thanks corion.	[reply] [d/l] [select]