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TartanLlama / optional

C++11/14/17 std::optional with functional-style extensions and reference support
https://tl.tartanllama.xyz
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'optional<T&>::and_then(F&& f) &&' calls f with lvalue reference #9

Closed rollbear closed 6 years ago

rollbear commented 6 years ago

This makes sense. The 'optional' is an rvalue, but its contained type remains an lvalue reference. I.e.

int i = 3; optional<int&>{i}.and_then([](int& r){return optional<int&>{++r});

The optional r-value still refers to 'i', which is not an r-value.