nl_tokens: Return list of type parameters with duplicates removed ( duplicate identifier errors are generated in the actual type checking functions ) .
pl_tokens: function getTypeParametersFromDeclaration ( typeParameterDeclarations ) { var <mask> = [ ] ; ts . forEach ( typeParameterDeclarations , function ( node ) { var tp = getDeclaredTypeOfTypeParameter ( node . symbol ) ; if ( ! ts . contains ( result , tp ) ) { result . push ( tp ) ; } } ) ; return result ; }