To give a specific example, the push_back() member functions of std::vector became constexpr in C++20.
https://en.cppreference.com/w/cpp/container/vector/push_back
1 Answers
One of the requirements of a constexpr function is that it can only call other constexpr functions.
So, this allows push_back() to be called from some other constexpr function that might, actually, return something useful.
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