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Create SwapWithoutTemp #1580
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Create SwapWithoutTemp #1580
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This boils down to
a ^= b b ^= a // a ^ b ^ b = a a ^= b // a^b^a = b
This is a nifty trick to know when for some reason, you need to avoid temporary variables / registers at all costs. But even then it's not necessarily useful; on x86 for example, alternative instructions like XCHG tend to be faster.
In JavaScript, it's not really useful; it will probably be slower than a normal swap. Also, there are no proper macros or similar; to make this function usable, you'd have to return [a, b], at which point you could just return [b, a] to swap a and b.
Besides, this is missing documentation and tests (which would fail, since JS is pass by value). Leaning towards rejection. @raklaptudirm what do you think?
The xor trick might be good content educationally speaking. That said, this pr is definitely not up to the standards we require here and the API is faulty. I want to keep this pr open in case they can change the code and the API to work well because I would welcome the inclusion of this idea into the repo.
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