what does this.allow = !1 and this.allow = !0 mean?

Question

I tried to understand some code. It begin like this:

function Drawing(varCanvas, varSize, varPrice) {
    var c = this;
    this.allow = !1;
    this.size = varSize;
    this.$canvas = varCanvas;
(.....)
    this.allow = !0;

I don't understand why the developer wrote "this.allow = !1;" I never seen this writing before.

That's shortcut way to write booleans, killing readability... — A. Wolff, Jul 15 '16 at 13:55
Ok I get it, Thanks for your answers. How do you write it to be more understandable ? — Souvir Ly, Jul 15 '16 at 13:59
Possible duplicate of [What does !1 and !0 mean in Javascript?](http://stackoverflow.com/questions/11550681/what-does-1-and-0-mean-in-javascript) — JJJ, Apr 08 '17 at 06:27

score 0 · Accepted Answer · answered Jul 15 '16 at 14:04

0

To be honest I have never seen this myself, but its effect is:

!1 is the same as false

!0 is the same as true

so instead of this.allow = !1; you could write this.allow = false;

answered Jul 15 '16 at 14:04

TehSphinX

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Thank you very much – Souvir Ly Jul 15 '16 at 14:05
1

It is usually used by JS minifiers to minify JS code size. A sane developer shouldn't write such code manually. – le_m Jul 15 '16 at 14:10

what does this.allow = !1 and this.allow = !0 mean?

1 Answers1