Is it safe to use //1 as Math.floor in CoffeeScript?

Question

I thought

Math.random() * (max-min) // 1

would be shorter and comfortable than

Math.floor Math.random() * (max-min)

But I'm not sure whether the former is safe or not.

dan · Accepted Answer · 2014-07-31 10:29:11Z

1

I didn't know about the // operator but if we take a look at the JavaScript output of both versions we see that they are equivalent.

First: Math.floor(Math.random() * (max - min) / 1);

Second: Math.floor(Math.random() * (max - min));

(Dividing a number by 1 in JavaScript has no effect)

answered Jul 31, 2014 at 10:29

dan

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Comments

Sylvain Leroux · Accepted Answer · 2014-07-31 15:11:14Z

0

That usage is explicitly supported by the specs. So it is quite safe to use // as you intend. To quote the doc:

To simplify math expressions [...] // performs integer division

And latter:

CoffeeScript        JavaScript
-------------------------------------

a // b              Math.floor(a / b)

Please note this operator was added in CoffeScript 1.7.0

answered Jul 31, 2014 at 15:11

Sylvain Leroux

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