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Object.is()

Baseline

20159

Object.is() 2

console.log(Object.is("1", 1));
// : false

console.log(Object.is(NaN, NaN));
// : true

console.log(Object.is(-0, 0));
// : false

const obj = {};
console.log(Object.is(obj, {}));
// : false

js
Object.is(value1, value2)

value1

1

value2

2

2

Object.is() 2 2

Object.is() == == "" == false true Object.is()

Object.is() === Object.is() === NaN === == -0 +0 NaN

Object.is()

js
//  1: === 
Object.is(25, 25); // true
Object.is("foo", "foo"); // true
Object.is("foo", "bar"); // false
Object.is(null, null); // true
Object.is(undefined, undefined); // true
Object.is(window, window); // true
Object.is([], []); // false
const foo = { a: 1 };
const bar = { a: 1 };
const sameFoo = foo;
Object.is(foo, foo); // true
Object.is(foo, bar); // false
Object.is(foo, sameFoo); // true

//  2: 
Object.is(0, -0); // false
Object.is(+0, -0); // false
Object.is(-0, -0); // true

//  3: NaN
Object.is(NaN, 0 / 0); // true
Object.is(NaN, Number.NaN); // true

ECMAScript 2027 LanguageSpecification
# sec-object.is


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