Are there constants in JavaScript?

Question

Is there a way to use constants in JavaScript?

If not, what\'s the common practice for specifying variables that are used as constants?

Answer 1

ECMAScript 5 does introduce Object.defineProperty:

Object.defineProperty (window,'CONSTANT',{ value : 5, writable: false });

It's supported in every modern browser (as well as IE ≥ 9).

See also: Object.defineProperty in ES5?