Perl comes with B::Deparse 
$ perl -e " print ''=~/.*/ and ''=~/bar/ "
1
$ perl -MO=Deparse -e " print ''=~/.*/ and ''=~/bar/ "
'' =~ /bar/ if print '' =~ /.*/;
-e syntax OK

$ perl -MO=Deparse,-p -e " print ''=~/.*/ and ''=~/bar/ "
(print(('' =~ /.*/)) and ('' =~ /bar/));
-e syntax OK

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In reply to Re: perl regular expressions and empty strings unexpected results by Anonymous Monk
in thread perl regular expressions and empty strings unexpected results by bdimych

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