Yet another way to do it is to use a hash (which in OP's case seem out of proportion) ... 

my $string = 'bulky axe';

my %map = ( 'a' => 2 , 'b' => 4 );
$string =~ s/$_/$map{ $_ }/g for keys %map;

[download]

And, Python may have a solution for your "white, ugly braces" problem.

In reply to Re: ugly code by parv
in thread ugly code by fubber

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