nonLength
function nonLength(value: unknown): boolean;
nonLength(value) is the same test as !isLength(value), written so that a guard clause reads as a sentence rather than as a negation.
A whole number from 0 up to Number.MAX_SAFE_INTEGER — the range a length property may hold.
isX and nonX answer a question and never interrupt control flow; requireX and requireNonX hand the value back or throw. The scheme is explained in Validation conventions.
Parameters
Parameter | Type | Description |
|---|---|---|
|
| The value to check. |
Returns
boolean — true when the value is not a valid array-like length; otherwise false.
Examples
What passes and what does not
nonLength(-1); // => true
nonLength(1.5); // => true
nonLength("3"); // => true
nonLength(0); // => false
nonLength(42); // => false
nonLength(Number.MAX_SAFE_INTEGER); // => false
See also
Source
23 September 2026
This documentation was generated with AI (Claude) from the library's source code.