http://stackoverflow.com/a/36871623/5244995
Symbol.call = Symbol.call || Symbol('call');
Symbol.construct = Symbol.construct || Symbol('construct');
class Callable extends Function {
constructor(name) {
super();
// source: http://stackoverflow.com/a/36871623/5244995
// Generalized by J F, https://runkit.com/j-f • http://stackoverflow.com/u/5244995
// Support: http://caniuse.com/#feat=proxy (Edge 12+, Firefox 18+, Chrome 36+, Safari 10+)
// There does not appear to be a polyfill.
const pxy = new Proxy(this, {
apply(target, thisArg, args) {
return (target[Symbol.call] || (() => {})).apply(target, [thisArg, ...args]);
},
construct(target, args, newTarget) {
return (target[Symbol.construct] || (() => {})).apply(target, [newTarget, ...args]) || newTarget;
}
});
Object.defineProperty(pxy, 'name', {value: name})
return pxy
}
}
class Smth extends Callable {
constructor(x) {
super('hello');
this._x = x;
}
[Symbol.call]() {
return this._x
}
[Symbol.construct](newTarget) {
newTarget._x = this._x;
}
}
const smth = new Smth(256); // 256
smth()
typeof smth
smth instanceof Smth
smth instanceof Function
Object.getPrototypeOf(smth)
smth.name = 'test'
smth.name
const newsmth = new smth()
newsmth()
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