size (Lodash Compatibility)

Use .length property

This size function operates complexly due to null, undefined handling and support for various types.

Instead, use the faster and more modern .length property or Object.keys().length.

Returns the size of arrays, strings, and objects.

const length = size(collection);

Reference

size(collection)

Use size to check the size of arrays, strings, objects, Maps, and Sets. It provides consistent size information for various types of collections.

import { size } from 'es-toolkit/compat';

// Number of elements in an array
size([1, 2, 3]);
// Returns 3

// Number of characters in a string
size('hello');
// Returns 5

// Number of enumerable properties in an object
size({ a: 1, b: 2, c: 3 });
// Returns 3

// Number of elements in a Map
size(
  new Map([
    ['a', 1],
    ['b', 2],
  ])
);
// Returns 2

// Number of elements in a Set
size(new Set([1, 2, 3]));
// Returns 3

null or undefined returns 0.

import { size } from 'es-toolkit/compat';

size(null); // 0
size(undefined); // 0
size({}); // 0
size([]); // 0

Parameters

• collection (object | string | null | undefined): The array, string, object, Map, or Set to check the size of.

Returns

(number): Returns the size of the collection. Returns 0 if null or undefined.