code: function Class(ctor) {
          if (is('Object', ctor)) {
              // no constructor function passed, let's fall back to a default
              return Class(null, ctor);
  
          } else {
              return base(arguments, ctor || function() {});
          }
      }
docs: Class (constructor, [base1[, base2[, ... baseN]],], [methods]) Class (constructor, [base1[, base2[, ... baseN]],]); Class (methods)