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• Why does std::is_const<const int&>::value evaluate to false? 2 answers

Why does this static assertion fire?

static_assert(std::is_const<const int&>::value, "Pain");

Would be awesome to get both a syntactic (why the implementation would do this) and a semantic reasoning (why they would have designed this type trait's interface to do this).

I am aware it is possible to throw in a std::remove_reference call to get the expected outcome, but I'm not sure why that's necessary.