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How do I escape meta-characters in a user-defined string?

by Kozz (Friar)
on Mar 25, 2000 at 00:49 UTC ( #6100=categorized question: print w/replies, xml ) Need Help??
Contributed by Kozz on Mar 25, 2000 at 00:49 UTC
Q&A  > regular expressions


In the example below, the results are I found a match: "a" I found a match: "b" There was no match for "a+b" Now, the problem is that the + in the third key of the hash is being interpreted as a description of the regular expression, not as a literal character. If I have a large hash which contains these types of meta-characters in the keys, how do I escape those meta-characters to prevent them being interpreted?
#!/usr/bin/perl my %hash=( 'a', '2', 'b', '5', 'a+b', '7', ); my $string='a+b'; my $key; foreach $key (keys %hash){ if($string=~/$key/){ print "I found a match: \"$key\"\n"; }else{ print "There was no match for \"$key\"\n"; } }

Answer: How do I escape meta-characters in a user-defined string?
contributed by btrott

Quotes the metacharacters.

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