C Macro equivalent in Javascript

Question

The following macro is to determine if two numbers have the same sign, is for 2's complement number representation.

#define SAME_SIGNS( a, b )  (((long) ((unsigned long) a ^ (unsigned long) b)) >= 0 )

Can anyone suggest a javascript equivalent function?

In other words -- Could someone please translate that macro in javascript function? — user2533495, Jun 28 '13 at 22:28
literal translate: `function sameSigns(a, b) { return (((a >>> 0) ^ (b >>> 0)) | 0) >= 0; }` // But notice that a, b are FLOAT in NOT INTEGER, so the implementation is wrong somehow. — tsh, May 31 '17 at 05:31

Virus721 · Accepted Answer · 2013-06-28T23:04:47.530

1

(a < 0 === b < 0)

or

(a * b > 0) // If one of a or b is 0, can't tell.

or

(a < 0 && b < 0 || a > 0 && b > 0)

true -> same, else different

edited Jun 28 '13 at 23:04

answered Jun 28 '13 at 22:28

Virus721

Shorter version with no risk of overflow `return ((a<0) == (b<0));` (Adapted from [Rik](http://stackoverflow.com/users/5409/rik)'s [answer](http://stackoverflow.com/a/67498/664577)) – Anthony Accioly Jun 28 '13 at 22:46
Nailed it :). I suggest you to update your answer. – Anthony Accioly Jun 28 '13 at 22:55

score 0 · Answer 2 · answered Jun 28 '13 at 22:27

0

It won't be exactly the same, but how about something like !(a*b<0)?

answered Jun 28 '13 at 22:27

amaurea

2 Answers2