concepts.h

 
#pragma once
 
#include <concepts>
 
namespace smats {
 
template <class T>
concept IsEnum = std::is_enum_v<T>;
 
template <class T, class... U>
concept IsAnyOf = (std::same_as<T, U> || ...);
 
template <class T, class... U>
concept IsNotAnyOf = !IsAnyOf<T, U...>;
 
template <class T>
concept Arithmetic = requires(T a, T b) {
  { a + b } -> std::convertible_to<T>;
  { a - b } -> std::convertible_to<T>;
  { a* b } -> std::convertible_to<T>;
  { a / b } -> std::convertible_to<T>;
};  // NOLINT(readability/braces) per C++ standard concept definition
 
template <class T>
concept Numeric = std::totally_ordered<T> && Arithmetic<T>;
 
template <class T>
concept InvocableHashAlgorithm = requires(T t, const void* data, size_t length) {
  typename T::result_type;
  { t(data, length) } noexcept -> std::same_as<void>;
  { size_t() } noexcept -> std::same_as<typename T::result_type>;
};  // NOLINT(readability/braces) per C++ standard concept definition
 
template <class T, class U>
concept Hashable = requires(T t, U& hasher) {
  { t.hash(hasher) } noexcept -> std::same_as<void>;
} && InvocableHashAlgorithm<U>;
 
template <class T>
concept Spannable = std::ranges::contiguous_range<T> && std::ranges::sized_range<T>;
 
template <class T, class U>
concept SpannableOfType = Spannable<T> && std::same_as<U, std::ranges::range_value_t<T>>;
 
}  // namespace smats