they want the function has the ability to know how they're called, normal function? or pipeline? and they want to have different call other in those two cases:

onClick: xxx(prevent(listener)) |> stop |> yyy,

I don't know what exact he want, but someone mentioned new.target. The function can be aware of that if they're called like new f() or f()

This reminds me that we can also use Meta property (although I'm not sure if it is a good idea) to behave differently as a custom matcher. for example

function f(x) {
if (function.matches) return function.matches(x.__val__)
// { matches: true, value: x.__val__ } ?

return x.__val__
}