[removed] constant properties

Question

In javascript, can I declare properties of an object to be constant?

Here is an example object:

   var XU = {
      Cc: Components.classes
   };
<         


        

Answer 1

UPDATE: This works!

const FIXED_VALUE = 37;
FIXED_VALUE = 43;
alert(FIXED_VALUE);//alerts "37"

Technically I think the answer is no (Until const makes it into the wild). You can provide wrappers and such, but when it all boils down to it, you can redefine/reset the variable value at any time.

The closest I think you'll get is defining a "constant" on a "class".

// Create the class
function TheClass(){
}

// Create the class constant
TheClass.THE_CONSTANT = 42;

// Create a function for TheClass to alert the constant
TheClass.prototype.alertConstant = function(){
  // You can’t access it using this.THE_CONSTANT;
  alert(TheClass.THE_CONSTANT);
}

// Alert the class constant from outside
alert(TheClass.THE_CONSTANT);

// Alert the class constant from inside
var theObject = new TheClass();
theObject.alertConstant();

However, the "class" TheClass itself can be redefined later on