You might consider assigning your matches into an array, and subscripting that programmatically. 

my %patterns = ( 123 => [ 1, 2, 3 ],
                 312 => [ 3, 1, 2 ] );
@matches = $string =~ /regexp/;
$string = join "", @matches[ @{ $patterns{$patternkey} } ];

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(You need error handling here, of course; and it probably makes sense to promote the scope of %patterns a bit so that it doesn't get constructed every time you enter the sub.)

In reply to Re: Double interpolation of captured substrings by gaal
in thread Double interpolation of captured substrings by bobf

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