$str = 'Nothing but perl can parse Perl'; print($str =~ /perl/gi ?1:0,"\n"); # Prints '1' print($str =~ /noth/gi ?1:0,"\n"); # Prints '0' print($str =~ /perl/i ?1:0,"\n"); # Prints '1' print($str =~ /noth/i ?1:0,"\n"); # Prints '1'