use strict;
my $str = 'Game.ObjectsById[1].buy
Game.shimmerTypes[\'golden\'].popFunc
Game.setVolume';
my $regex = qr/(?:^|\.)(\w+)(?:\['?"?(\w+)"?'?\])?/mp;
my $subst = '.$1[$2';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html