isEmpty

Checks if a value is empty.

Supported types:

• null / undefined → empty
• string → length === 0
• array → length === 0
• Map / Set → size === 0
• plain object → no own enumerable properties

Available since v2.0.0

Import

import { isEmpty } from '@helpers4/type';

Signature

isEmpty(value: unknown): value is "" | never[] | ReadonlyMap<never, never> | ReadonlySet<never> | null | undefined

Parameters

Parameter	Type	Description
value	unknown	The value to check

Returns

value is "" | never[] | ReadonlyMap<never, never> | ReadonlySet<never> | null | undefined — true if the value is considered empty, false otherwise. Acts as a type guard: the else branch narrows away null, undefined, empty strings, empty arrays, and empty Map/Set. Plain empty objects ({}) are not representable as a distinct type in TypeScript and are therefore not part of the predicate.

Examples

Check empty values

Returns true for null, undefined, empty strings, arrays, objects, Maps, and Sets.

isEmpty('')     // => true
isEmpty([])     // => true
isEmpty({})     // => true
isEmpty(null)   // => true

Non-empty values

Returns false for values with content.

isEmpty('hello') // => false
isEmpty([1])     // => false
isEmpty(42)      // => false

Name conflict

A helper named isEmpty also exists in @helpers4/array, @helpers4/object, @helpers4/string. If you need both in the same file, rename at import with as:

import { isEmpty as isEmpty4type } from '@helpers4/type';
import { isEmpty as isEmpty4array } from '@helpers4/array';
import { isEmpty as isEmpty4object } from '@helpers4/object';
import { isEmpty as isEmpty4string } from '@helpers4/string';

See Name Conflicts for the full resolution guide.

Source

View source on GitHub