Have a look at eval. Something like this (untested) should work as you desire. I don't think you need the block eval but do not have the ability to test. eval has security implications. 

eval{ eval "(\$output = \$string) =~ s/\$regexp/\$new/$suffix" };

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In reply to Re: unconventional string substitutions by tachyon-II
in thread unconventional string substitutions by halfcountplus

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