Low Level Bit Hacks You Absolutely Must Know

Re:Low Level Bit Hacks You Absolutely Must Know by tripletao on Friday May 11, 2018 @11:53PM (#17052397)

The trick is to let your "double" only take on values that are also valid 32-bit integers, like with lots of gratuitous (x|0) and stuff. That excludes your (indeed problematic) -0. JavaScript's semantics give you enough to implement 32-bit integer math this way pretty easily. The speed may vary dramatically with small changes to the compiler, but correctness won't.

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Re:Low Level Bit Hacks You Absolutely Must Know by slededit on Saturday May 12, 2018 @12:21AM (#17052453)

I still stick by my original point that:

((int)dblval) & flag

would require serious justification in a C code review. In JS its all you have. Under those restrictions I'd use it as rarely as possible. But yes you can use it correctly if you try.

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Re:Low Level Bit Hacks You Absolutely Must Know by tripletao on Saturday May 12, 2018 @01:15AM (#17052591)

That's certainly true. The only reason to play these games is that JavaScript gives you no better option.

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