I think there is a better way of doing this, but I couldn't think of it. I have a string where I need to rewrite each occurence of [string] with the following:

__[username]__[string]__

There can be multiple instances of [string] in a line, and I don't want to match [string] a second time once it's been rewritten.

Here is what I am doing now. I know there has got to be a better way, but this does work. 

my $prefix = "__" . $self->{user} . "__";
   my $suffix = "__";
   my %hash;
   my $c =0;
   my @contexts = sort {length $b <=> length $a} @list;
   foreach my $context (@contexts) {
      if($var_val =~s/($context?)/\@\@$c\@\@/g) {
         $hash{$c} = "$prefix$1$suffix";
         $c++;
      }
   }
   foreach my $key (keys %hash) {
      $var_val =~s/\@\@$key\@\@/$hash{$key}/g;
   }

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In reply to Regex help by snacktime

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