nonEmpty
function nonEmpty(value: unknown): boolean;
nonEmpty(value) is the same test as !isEmpty(value), written so that a guard clause reads as a sentence rather than as a negation.
Emptiness is read per kind: null and undefined, a string with nothing but whitespace, an array, Set or Map with no entries, an object with no own keys. 0 and false are values, not emptiness.
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 empty; otherwise false.
Examples
What passes and what does not
nonEmpty(0); // => true
nonEmpty(false); // => true
nonEmpty("a"); // => true
nonEmpty([0]); // => true
nonEmpty(null); // => false
nonEmpty(""); // => false
nonEmpty(" "); // => false
nonEmpty([]); // => false
nonEmpty({}); // => false
nonEmpty(new Map()); // => false
See also
Source
23 September 2026
This documentation was generated with AI (Claude) from the library's source code.