Всем привет, подскажите что означает следующая запись:
var x = ( () => this );
увиденная мной при просмотре документации MDN к "this", раздел "
Arrow functions"?
Вот сам пример оттуда:
// Create obj with a method bar that returns a function that
// returns its this. The returned function is created as
// an arrow function, so its this is permanently bound to the
// this of its enclosing function. The value of bar can be set
// in the call, which in turn sets the value of the
// returned function.
var obj = {
bar: function() {
var x = (() => this);
return x;
}
};
// Call bar as a method of obj, setting its this to obj
// Assign a reference to the returned function to fn
var fn = obj.bar();
// Call fn without setting this, would normally default
// to the global object or undefined in strict mode
console.log(fn() === obj); // true
// But caution if you reference the method of obj without calling it
var fn2 = obj.bar;
// Calling the arrow function's this from inside the bar method()
// will now return window, because it follows the this from fn2.
console.log(fn2()() == window); // true
По возможности дайте ссылку где можно про это прочитать. Заранее спасибо!
