isUndefined#

Check if the given value is undefined.

Usage Scenarios#

• Default Parameter Handling: Check for undefined before applying defaults.
• Optional Property Checking: Verify if object properties exist.
• Error Prevention: Avoid undefined reference errors.

Examples#

import { isUndefined } from 'funtool';

isUndefined(undefined); // ✅ true
isUndefined(null); // ❌ false
isUndefined(0); // ❌ false
isUndefined(''); // ❌ false

Signature#

function isUndefined(v: any): boolean

Parameters#

• v (any): The value to test if it is undefined.

Returns#

• (boolean): Returns true if the value is undefined, otherwise returns false.