Thanks for the great reply. It works well. However when I cut it down to this, it doesn't work: 
  $string = '$a $b $c';
  $hash{a} = "go";
  $string =~ s{\$(\w+)}{$$hash{$1}}ge;

[download]
Could it be the hash reference you use to the subroutine? \$hash ? Thanks.

In reply to Re^2: Replacing string with regexp without using modules by cowgirl
in thread Replacing string with regexp without using modules by cowgirl

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