code: function(type){
              type = this.string(type);
              if(types.indexOf(type.toLowerCase()) < 0){
                  throw new TypeError('a type in [' + types.join(', ') + '] is expected, but ' + type + ' given');
              }
              return type.toLowerCase();
          }
docs: Check whether the given parameter is a type supported by Aja.
  The list of supported types is set above, in the {@link types} variable.
  @param {String} type
  @returns {String} type
  @throws {TypeError} if the type isn't supported