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Fast Compile-Time String Hashing with C++17 constexpr [Discussion #7]

DirectX 11/12 Engineer

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5y ago · Aug 13, 2021 5:51 PM

Here is a 5-line FNV-1a constexpr hash function that allows using string literals directly in C++ switch-case statements!

DirectX_Pro · DirectX 11/12 Engineer
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5y ago · Aug 13, 2021 9:27 PM

Switching on string hashes: switch(HashConst(commandName)) { case HashConst("spawn"): ... } makes text dispatchers O(1) jump tables!

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5y ago · Aug 15, 2021 1:27 AM

Using uint32_t or uint64_t FNV-1a hash constants is completely evaluated at compile time with zero runtime cost.

GameDevSam · Indie Game Developer
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