JS isPrototypeOf

by Town December 19, 2018

JavaScript

function A() {}
function B() {}

B.prototype = Object.create(A.prototype);

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

console.log("b is prototype of a", b.isPrototypeOf(a)); // false
console.log("a is prototype of b", a.isPrototypeOf(b)); // false

console.log("b is prototype of A", b.isPrototypeOf(A)); // false
console.log("A is prototype of b", A.isPrototypeOf(b)); // false
console.log("A prototype is prototype of b", A.prototype.isPrototypeOf(b)); // true
console.log("b prototype is prototype of A", b.prototype.isPrototypeOf(A)); // syntax error

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JS isPrototypeOf

JavaScript

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