Assuming "foo" and "bar" are metasyntactic variables, and that the real substrings could be anything, the use of quotemeta is in order:

UPDATE: This paragraph should read…

Assuming "foo" and "bar" are metasyntactic variables representing literal substrings, and that the real literal substrings could be any literal substrings (not regular expression patterns), then the use of quotemeta is in order:
#!/usr/bin/perl
use strict;
use warnings;

my %edits = ( '***' => 'stars', '|||' => 'stripes' );
my $value = '*** and |||';
my $match = '(' . join('|', map { quotemeta } keys %edits) . ')';

$value =~ s/$match/$edits{$1}/g;

print $value; # Prints "stars and stripes"

[download]

(I realize this example is no longer swapping anything. Sorry.)

Jim

In reply to Re^2: Swap foo and bar in text? by Jim
in thread Swap foo and bar in text? by Cody Fendant

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