code: public static String minus(CharSequence self, Pattern pattern) {
          return pattern.matcher(self).replaceFirst("");
      }
docs: Remove a part of a CharSequence. This replaces the first occurrence
  of the pattern within self with '' and returns the result.
  
  @param self   a String
  @param pattern a Pattern representing the part to remove
  @return a String minus the part to be removed
  @since 2.2.0