[P3816] Implement std::consteval_hash<std::meta::info> (semi-stable implementation 2) - #195
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fullptr wants to merge 31 commits into
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[P3816] Implement std::consteval_hash<std::meta::info> (semi-stable implementation 2)#195fullptr wants to merge 31 commits into
std::consteval_hash<std::meta::info> (semi-stable implementation 2)#195fullptr wants to merge 31 commits into
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std::consteval_hash<std::meta::info> (simpler implementation)std::consteval_hash<std::meta::info> (semi-stable implementation)
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std::consteval_hash<std::meta::info> (semi-stable implementation)std::consteval_hash<std::meta::info> (semi-stable implementation)
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std::consteval_hash<std::meta::info> (semi-stable implementation)std::consteval_hash<std::meta::info> (semi-stable implementation 2)
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Implements https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3816r0.html in a way that is stable across repeated runs of the compiler on unchanged source code.
Provides a simpler implementation of https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2025/p3816r0.html compared to #170. The issue with the other implementation is the burden of keeping it updated; whenever a new construct becomes reflectable in the future, this implementation would also needed to be updated to account for it.
The simplest approach to defining the hash is just the hash the AST pointer that the
meta::inforepresents, but this results in unstable values across repeat compilations. However, we can just intern these with a map to produce stable values. This implementation does not need to be updated whenever new reflections are added to the language, and re-compiling source code without changes will still yield the same hash values as required by the paper.