anchor.diff:  
   
     Function _parseMethod(String method) {
  +
  +    var folder = (Function p, Match m) {
  +      if (p != null) {
  +        return p;
  +      }
  +      var f1 = _parseMethod(method.substring(0, m.start).trim());
  +      if (f1 == null) {
  +        return null;
  +      }
  +      var f2 = _parseMethod(method.substring(m.start + 2).trim());
  +      if (f2 == null) {
  +        return null;
  +      }
  +
  +      if (m[0] == "&&") {
  +        return (String value) {
  +          return f1(value) && f2(value);
  +        };
  +      } else {
  +        return (String value) => f1(value) || f2(value);
  +      }
  +
  +    };
  +
       if ((method.startsWith('pattern{') || method.startsWith("function-string{")) && method.endsWith("}") && new RegExp(r"[{}]").allMatches(method.replaceAll(r"\\", "").replaceAll(r"\{", "").replaceAll(r"\}", "")).length == 2) {
   
         if(method.startsWith("p")){
  
positive.code:       return core.nonEmpty;
      } else if (method.startsWith("(") && method.endsWith(")")) {
        return _parseMethod(method.substring(1, method.length - 1).trim());
      } else if (method.contains("&&") || method.contains("||")) {
        return new RegExp(r"(&&|\|\|)").allMatches(method).fold(null, (Function p, Match m) {
          if (p != null) {
            return p;
          }
          var f1 = _parseMethod(method.substring(0, m.start).trim());
          if (f1 == null) {
            return null;
          }
          var f2 = _parseMethod(method.substring(m.start + 2).trim());
          if (f2 == null) {
            return null;
          }
  
          if (m[0] == "&&") {
            return (String value) {
              return f1(value) && f2(value);
            };
          } else {
            return (String value) => f1(value) || f2(value);
          }
  
        });
      }
  
  
  
negative.code:         h.remove();
          return r;
        };
  
      } else if (method == "mail") {
        return core.validMail;
  