Callable object

callableObject-proxy.js

const wrapCallableObject = (() => {
  const wrapper = () => {
    throw new Error('Wrapper cannot be called');
  };
  return function wrapCallableObject(object) {
    if (object) {
      return object instanceof Function ? object : new Proxy(
          wrapper, {
            apply: (wrapper, thisObj, args) => {
              object.apply(thisObj, args);
            }
          });
    }
  };
})();
const wrapCallableObjectClass = (() => {
  const construct = (target, args) => {
    return wrapCallableObject(new target(...args));
  };
  return function wrapCallableObject(definition) {
    return new Proxy(
        definition, {
          construct
        });
  };
})();

CallableObject.js

class AbstractCallableObject {
  constructor() {
    return (...args) => this.apply(this, args);
  }

  apply(target, args) {
    this.call(target, ...args);
  }

  /*abstract*/ call(target, ...args) {
    throw new Error('Abstract .call() method cannot be called.');
  }
}