Brevity in JavaScript

awesome!

jsperf created by me:

http://jsperf.com/to-int

var
b = '1837727366484959938' | 0; // -1722178816

The purpose of your protip is vague, confusing, and not giving everyone the full story.

First, I have no idea why you are coercing a DOM node to an integer.

Second, if you want to coerce something to a number, you have the unary operator available which is more expressive. This does have the drawback of not truncating to an integer.

var b = +'1837727366484959938'; // 1837727366484959938
var b = +'1.5'; // 1.5

Lastly, as @couto pointed out, while numbers are 64-bit loating point in JS, the bitwise operators coerce those numbers in 32-bits.
As a result, you run into cases where you exceed 2^31, 2147483648 and entire into one's compliment territory.

Math.pow(2, 31) | 0; // -2147483648
(Math.pow(2, 31) - 1) | 0; // 2147483647

References:

https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Bitwise_Operators

http://www.amazon.com/JavaScript-Definitive-Guide-Activate-Guides/dp/0596805527/

Yeah, this only works for small numbers due to the way JS does it numbers. It uses the binary base. I will do a follow-up.

@prosperva: check http://www.2ality.com/2013/10/safe-integers.html