JavaScript: The Definitive Guide, Fourth Edition

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Name

Function.length — the number of declared arguments

Availability

JavaScript 1.1; JScript 2.0; ECMAScript v1

Synopsis

function.length

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.

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