Perl metaprogramming: when is it unsafe to use quotemeta on the REPLACEMENT value of s///?

Question

Perl\'s quotemeta operator typically works on the SEARCH side of s///, but in generating code to be compiled with eval, how should I protect the REPLACEMENT tha

Answer 1

As far as I can tell, perl doesn't do magic things with $replace as long as you don't add the /e flag on the substitute. So quotemeta will always change your result, as it then contains a lot of backslashes.

#!/usr/bin/perl

$test="test";

$literal_replacement='Hello $1, or \1';
my $replace = quotemeta $literal_replacement;
$test =~ s/test/$replace/;

print $test,"\n";

returns:

Hello\ \$1\,\ or\ \\1

Which is probably not what you want :