fun <A1, A2, A3, A4, R> f4(f: KFunction4<A1, A2, A3, A4, R>, a1: A1, a2: A2, a3: A3, a4: A4): MetaFeature<R> (source)
Creates a MetaFeature for the given function f which expects 4 arguments.
Notice for expectation function writers: you should use feature and pass a
class reference instead of using this convenience function (e.g. feature(MyClass::fun, ...)).
This way we are always able to report the function name, even if the subject is not defined which occurs if a
previous transformation of the subject could not be carried out.