Why does `Array.length`, `Function.length`, `String.length`, etc return 1?

Posted by zealoushacker on Stack Overflow See other posts from Stack Overflow or by zealoushacker
Published on 2012-10-30T20:45:49Z Indexed on 2012/10/30 23:01 UTC
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JavaScript

While teaching my JavaScript class yesterday, my students and I came across some interesting functionality that I thought might be worth capturing in a question and the answer I've come to.

Typing Array.length in the JS console in chrome returns 1.

Likewise, Function.length returns 1. This is important because:

Every function in JavaScript is actually a Function object. (MDN JS Ref: Function)

Thus, Object.length and likely all other native objects will and should return 1 as the value of the length property.

So, finally why is this behavior occurring?

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Developer IT

Why does `Array.length`, `Function.length`, `String.length`, etc return 1? - Developer IT

Why does `Array.length`, `Function.length`, `String.length`, etc return 1?

JavaScript

Related posts about JavaScript

CHAT ROOMs 7 by 6

Integrating JavaScript Unit Tests with Visual Studio

Has Javascript developed beyond what it was originally designed to do?

PHP, javascript, single quote problems with IE when passing variable from ajax post to javascript fu

Javascript in XSL that is loaded by Javascript

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