class - Override default behavior of comparison operators in JavaScript

Question

I have a custom Javascript class (created using John Resig's Simple Javascript Inheritance). I want to be able to compare two instances of this class, using the ==, <, >, >=, and <= symbols.

How do I override the comparators of my custom class?

Answer 1

Try overriding valueOf(). Then you can write stuff like this:

if (obj1.valueOf() === obj2.valueOf())
if (obj1.valueOf() < obj2.valueOf())
if (obj1.valueOf() > obj2.valueOf())

So whenever I need a special JavaScript object type to override the comparison I just add valueOf to the prototype. It works great for primitive types as well since valueOf just returns the value.

Just watch out for nulls.