* @param pattern the path pattern string from robots.txt (may contain * and $)
         */
        public PathPattern(final String pattern) {
            this.pattern = pattern;
            this.regexPattern = compilePattern(pattern);
            this.priorityLength = calculatePriorityLength(pattern);
        }

        /**
         * Compiles a robots.txt path pattern into a regular expression pattern.

  private static final class ContainsPatternFromStringPredicate extends ContainsPatternPredicate {

    ContainsPatternFromStringPredicate(String string) {
      super(Platform.compilePattern(string));
    }

    @Override
    public String toString() {
      return "Predicates.containsPattern(" + pattern.pattern() + ")";
    }