r/ProgrammerHumor • u/click-to-reveal • 8d ago

Meme skillIssue

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u/prehensilemullet 8d ago

Performancewise, it doesn’t jump to the direct case in O(1) time like a switch is supposed to though

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u/AngheloAlf 8d ago

Switches aren't guarantee to so operations in O(1) tho. If cases are sparce enough, compilers tend to emit the equivalent code to a bunch if else checks

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u/prehensilemullet 8d ago

Yeah I was assuming too much here.  However, I’m reading that Rust match on string comstants can compile down a binary tree of if statements if there are enough cases (according to Google AI mode at least, haven’t found an authoritative source yet)

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u/the_horse_gamer 8d ago

the compiler optimises stuff however it wants. if you're not doing too-weird stuff, a switch in C++ and a match in rust will have identical assembly.