Question

I searched if JavaScript offers a mean to define symbolic constants, but didn’t find anything. Did I miss something ?

Is it a common practices to use const var instead ?

var const MAXIMUM_VALUE = 100;  

Thanx.

Answer 1

const is not supported by IE, so if you want to support IE that is out of the question.

As far as I know, and the best way of doing this to keep it simple is to just have a naming convention for your constants like the ever-popular ALL UPPERCASE. There are some examples out there to force constants but they are not worth it for the most part. Alternatively, you could use a function:

function myConst() { return 'myValue'; } 

This can of course still be overridden but I’ve seen it used.

Also see:

• Are there constants in Javascript?
• Is it possible to simulate constants in Javascript using closures?
• Javascript: final / immutable global variables?