Is there a way to add "subproperties" to a variable in JS?

Question

I was asking myself if there is a way to add something like a subproperty to a variable. Here is an example of what I want to achive:

var variable = 5;
variable.property = "what ever...";
console.log(variable); //outputs 5
console.log(variable.property); //outputs "what ever..."

(The data types aren't important...)

Is there maybe a way to achive this using getters or Proxys, and does my variable need to be an object or not?

Hopefully you can help and there is a way to do this :)

you can set variable as { value: 5 } initially, then use variable.value to output 5 — Brian, Jan 09 '17 at 18:05
If the variable is not a primitive type (e.g. `Number`, `String`, `Boolean`), then that will work (except that your second `var` keyword is not appropriate.) Everything else descends from `Object`, where this is normal. ([There are exceptions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze), BTW, but probably not important here.) It might not always be a good idea, but it should work. With primitives, you will be able to set the value, but it immediately disappears. — Scott Sauyet, Jan 09 '17 at 18:08
Not directly on a primitive, though you can modify Number.prototype, this is also unadvisable if this question is for anything more than curiosity's sake. — Damon, Jan 09 '17 at 18:18

score 1 · Accepted Answer · edited May 23 '17 at 12:13

You can add ad-hoc properties to any variable which points to an Object. You should also read up on prototype if you're interested in using class-like objects: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/prototype

However, your example uses the number 5, which is a Primitive. You cannot assign properties to Primitives: https://javascriptweblog.wordpress.com/2010/09/27/the-secret-life-of-javascript-primitives/

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