JavaScript: The Definitive Guide

24.86. Function.length: the number of declared arguments

ECMAScript v1

24.86.1. Synopsis

function.length

24.86.2. Description

The length property of a function specifies the number of named arguments declared when the function was defined. The function may actually be invoked with more than or fewer than this number of arguments. Don't confuse this property of a Function object with the length property of the Arguments object, which specifies the number of arguments actually passed to the function. See Arguments.length for an example.

24.86.3. See Also

Arguments.length