nl_tokens: find method with given name from base classes
pl_tokens: function superMethod ( methodname ) { var func = null ; var p = this . __proto__ ; if ( ! p ) throw new Error ( 'invalid parameters' ) ; for ( p = p . __proto__ ; ! isEmpty ( p ) ; p = p . __proto__ ) { var <mask> = p [ methodname ] ; if ( typeof method === 'function' ) { func = method ; break ; } } if ( ! func ) throw new Error ( 'super method not found: ' + methodname ) ; return func ; }