my @temp = $str =~ m{ ([\+\-])? (?# Sign) (P) (?# 'P' for period? This is our magic character) (?: (?:(\d+)Y)? (?# Years) (?:(\d+)M)? (?# Months) (?:(\d+)W)? (?# Weeks) (?:(\d+)D)? (?# Days) )? (?:T (?# Time prefix) (?:(\d+)H)? (?# Hours) (?:(\d+)M)? (?# Minutes) (?:(\d+)S)? (?# Seconds) )? }x;