Is 'bol === !0' and 'bol == true' the same?

Question

Is bol === !0 exactly the same as bol == true?

Example:

function myFunction(bol){
    if(bol===!0){
        return 1;
    }else{
        return -1;
    }
}

alert(myFunction(true));//1

Will I ever run into problems if I decide to use it? (different than code readability)

possible duplicate of [JavaScript === vs == : Does it matter which "equal" operator I use?](http://stackoverflow.com/questions/359494/javascript-vs-does-it-matter-which-equal-operator-i-use) — Matt Ball, Jan 14 '12 at 01:37
Don't use `!0` for `true` - a two-character saving is not worth the loss in readability. If you want `true` just say `true`. — nnnnnn, Jan 14 '12 at 02:54
Some JS compressors use `!0` and `!1` to save a couple bytes. — user123444555621, Jan 14 '12 at 03:19

Tikhon Jelvis · Accepted Answer · 2012-01-14T01:44:29.857

3

No. 1 == true is true but 1 === !0 is false.

Since !0 is true, this is equivalent to bol === true. Note how you should still use the three equal signs to get exactly the same behavior.

The === means JavaScript will not try to coerce the values when comparing. If you actually want to coerce, you would use ==. However, in this case, the if will just coerce for you:

if (bol) { ... }

is basically the same as

if (bol == true) { ... }

edited Jan 14 '12 at 01:44

answered Jan 14 '12 at 01:35

Tikhon Jelvis

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so `bol === !0` === `bol === true`? – mithril333221 Jan 14 '12 at 01:44
Yes, because you evaluate `!0` first, which is equal to `true`. – Tikhon Jelvis Jan 14 '12 at 01:47

Is 'bol === !0' and 'bol == true' the same?

1 Answers1