apps-script-utils 2.1.1 Help

requireNumber

function requireNumber(value: unknown, message: string = "Expected a number."): number;

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

value

unknown

The value to validate.

message (optional) = "Expected a number."

string

The message of the exception. A default is used when omitted.

Returns

number — the same value, typed as a number.

Throws

Exception

Condition

IllegalArgumentException

the value is not a number.

Examples

What passes and what does not

requireNumber(0); // => 0 requireNumber(1.5); // => 1.5 requireNumber("1"); // throws IllegalArgumentException requireNumber(null); // throws IllegalArgumentException

See also

Source

src/lang/base/requireNumber.ts

23 September 2026
requireNullrequireNumberLike

This documentation was generated with AI (Claude) from the library's source code.