@keywords a, of, is, has, prefix .

@prefix : <http://yosi.us/lambda#> . 
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

{?x a RootExpression; eval ?y} => {?x eval ?y} .

{
 ?X results ?R } 
=>
{?X results ?R } .