Defined in header <concepts> | ||
|---|---|---|
template <class R, class T, class U> concept relation = std::predicate<R, T, T> && std::predicate<R, U, U> && std::predicate<R, T, U> && std::predicate<R, U, T>; | (1) | (since C++20) |
The concept relation<R, T, U> specifies that R defines a binary relation over the set of expressions whose type and value category are those encoded by either T or U.
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