Here is a new version of the comment-matching program which was given earlier (regex3a.rb); this has now been adapted to use the value of the group (*.) which returns all the characters (zero or more) following the string matched by the preceding part of the regular expression (which here is: ^s*#). This matches zero or more whitespace (s*) characters from the start of the current line (^) up to the first occurrence of a hash or pound character: #: