Create dictionary of local variables in Javascript

Question

I realize there is no way to get a dictionary of local variables in a javascript function, and no equivalent of python's locals(). However, is there a way to write a function that would assist in this. For example, something like:

var a = 1;
var b = 2;

var output = locals(a, b);
console.log(output);

And output would be a dictionary with all the variables:

{
    "a": 1,
    "b": 2
}

Or, any other way apart from me manually creating a map, and inserting each field.

As the questions you link to say: No. JS provides no mechanisms for inspecting what variables exist (other than globals when they are added to the default object as a side-effect) — Quentin
– Quentin, Commented Nov 25, 2019 at 18:35
If you are going to make a static function call, referencing the variables, you can use the short property syntax of the object literal: const output = { a, b } — Christian C. Salvadó
– Christian C. Salvadó, Commented Nov 25, 2019 at 18:36
@Quentin, I am not asking to inspect the variables in scope. I understand that is not possible. I am asking if there is a way to create a helper method to assist with creating a dictionary of specified local variables. The method will be passed all the variables of interest. So, this question is not really a duplicate. — rouble
– rouble, Commented Nov 25, 2019 at 18:39

Quentin · Accepted Answer · 2019-11-25 18:42:14Z

4

No.

Since you can't pass variables (only values) the data passed to such a function would be 1 and 2 with no association with the variable name.

You can, however, use the shorthand object syntax:

const output = { a, b };

… where an identifier without a value will take its value from the variable of the same name.

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