Access Hash value when key is a number with undescore (1_1)

Question

When I have this:

hash = { 1_1: 'foo' }

why hash[1_1] gives undefined, while for ex.:

hash = { 1: 'foo' }

hash[1] returns correct value.

Both objects keys are strings:

typeof Object.keys(hash)[0]  /// -> string

so why it doesnt convert hash[1_1] to string?

p.s. I tested on Chrome and looks like it already supports numeric separators

Code is written not by me, so I am jst wondering how to go here when previously keys were only numbers, but now they also come as `2_4` — bigInt, Jun 21 '19 at 14:43

score 3 · Accepted Answer · answered Jun 21 '19 at 14:39

3

JS engine is disposing of the underscore and converting the key from 1_1 to 11. But if you wrap it in quotes, it will work:

hash = {"1_1": 'foo' }

//{1_1: "foo"}

answered Jun 21 '19 at 14:39

Tanner

Thats a good catch, I was just hoping I can avoid something like `function(param) { hash[ '' + param] // do something }` – bigInt Jun 21 '19 at 14:47
@NinaScholz My example came from Chrome - but testing in IE and Edge yield the same result. – Tanner Jun 21 '19 at 15:27

1 Answers1