an example of instance as a callable function

InstanceAsFunction.js

class MyClass {}

class FunctionAsInstance extends MyClass {
	constructor(...args) {
		super();

		const me = this;
		this.args = args;

		const callable = function (_args) {
			me._args = _args;
			return me;
		};
		
		Reflect.setPrototypeOf(callable, me);
		return callable;
	}
}


const me = new FunctionAsInstance(123);

try {
	const result = me(123);
	console.log(result instanceof FunctionAsInstance);
	console.log(result instanceof MyClass);
	console.log(result.args);
	console.log(result._args);
} catch (e) {
	debugger;
}

InstanceProxyAsFunction.js

class MyClass {}

class FunctionAsInstance extends MyClass {
	constructor() {
		super();

		const me = this;

		const callable = function () {
			return me;
		};
		
		callable.prototype = me;
		callable.prototype.constructor = FunctionAsInstance;
		
		return new Proxy(callable, {
			get (target, prop) {
				return Reflect.get(me, prop)
			},
			set (target, prop, value) {
				Reflect.set(me, prop, value)
			}
		});
	}
}


const me = new FunctionAsInstance;
try {
	const result = me(123);
	console.log(result instanceof FunctionAsInstance);
	console.log(result instanceof MyClass);
} catch (e) {
	debugger;
}