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(===)

Baseline

20157

(===) 2

console.log(1 === 1);
// : true

console.log("hello" === "hello");
// : true

console.log("1" === 1);
// : false

console.log(0 === false);
// : false

js
x === y

(=== !==) IsStrictlyEqual

  • false
  • true
  • null undefined true
  • NaN false
  • 2
    • +0 -0
    • true false

(==) ==

js
"hello" === "hello"; // true
"hello" === "hola"; // false

3 === 3; // true
3 === 4; // false

true === true; // true
true === false; // false

null === null; // true

js
"3" === 3; // false
true === 1; // false
null === undefined; // false
3 === new Number(3); // false

js
const object1 = {
  key: "value",
};

const object2 = {
  key: "value",
};

console.log(object1 === object2); // false
console.log(object1 === object1); // true

ECMAScript 2027 LanguageSpecification
# sec-equality-operators


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