requireNonNumber
function requireNonNumber<T>(
value: T | number,
message: string = "Expected a non-numeric value."
): T;
The test is typeof value === "number", which NaN and both infinities satisfy. Use isFloat, isInteger or isNaN when those cases have to be told apart.
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 validate. |
|
| The message of the exception. A default is used when omitted. |
Returns
T — the same value, with a number excluded from its type.
Throws
Exception | Condition |
|---|---|
| the value is a number. |
Examples
What passes and what does not
requireNonNumber("1"); // => "1"
requireNonNumber(null); // => null
requireNonNumber(0); // throws IllegalArgumentException
requireNonNumber(1.5); // throws IllegalArgumentException
See also
Source
23 September 2026
This documentation was generated with AI (Claude) from the library's source code.