c:\@Work\Perl\monks>perl -wMstrict -le "my @foos = (':X,{X', ':X,{'); ;; for my $foo (@foos) { printf qq{'$foo' -> }; $foo =~ s( (?<= [:,{]) (?= .) ){.}xmsg; print qq{'$foo'}; } " ':X,{X' -> ':.X,.{.X' ':X,{' -> ':.X,.{'