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javascript instance method

Set.prototype.add()

View on MDN ↗

The add() method of Set instances inserts the specified value into this set, if it is not already present.

Interactive exampleOpen the canonical MDN source to run this embedded demo.
const set = new Set();

set.add(42);
set.add(42);
set.add(13);

for (const item of set) {
  console.log(item);
  // Expected output: 42
  // Expected output: 13
}

Syntax

add(value)

Parameters

  • value
    • : The value to add to the Set object. Objects are compared by reference, not by value.

Return value

The Set object.

Examples

Using add()

const mySet = new Set();

mySet.add(1);
mySet.add(5).add("some text"); // chainable

console.log(mySet);
// Set [1, 5, "some text"]

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also