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new.target

Baseline Widely available

This feature is well established and works across many devices and browser versions. Its been available across browsers since 2017 ..

new.target new. new, new.target . new.target undefined.

In this article

new.target

new.target new, , target. new , new . , new.target new new .

new.target . , new.target new.target .

new.target

( ), new.target undefined. new .

js
function Foo() {
  if (!new.target) throw "Foo() must be called with new";
  console.log("Foo instantiated with new");
}

new Foo(); //  "Foo instantiated with new"
Foo(); //  "Foo() must be called with new"

new.target

, new.target , new. , new.target , .

js
class A {
  constructor() {
    console.log(new.target.name);
  }
}

class B extends A {
  constructor() {
    super();
  }
}

var a = new A(); //  "A"
var b = new B(); //  "B"

Specification
ECMAScript 2027 LanguageSpecification
# sec-built-in-function-objects

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