diff options
Diffstat (limited to 'absl/types/compare.h')
| -rw-r--r-- | absl/types/compare.h | 150 |
1 files changed, 99 insertions, 51 deletions
diff --git a/absl/types/compare.h b/absl/types/compare.h index 50361d623025..a213e0b0b682 100644 --- a/absl/types/compare.h +++ b/absl/types/compare.h @@ -79,79 +79,72 @@ enum class ord : value_type { less = -1, greater = 1 }; enum class ncmp : value_type { unordered = -127 }; +// Define macros to allow for creation or emulation of C++17 inline variables +// based on whether the feature is supported. Note: we can't use +// ABSL_INTERNAL_INLINE_CONSTEXPR here because the variables here are of +// incomplete types so they need to be defined after the types are complete. +#ifdef __cpp_inline_variables + +#define ABSL_COMPARE_INLINE_BASECLASS_DECL(name) + +#define ABSL_COMPARE_INLINE_SUBCLASS_DECL(type, name) \ + static const type name + +#define ABSL_COMPARE_INLINE_INIT(type, name, init) \ + inline constexpr type type::name(init) + +#else // __cpp_inline_variables + +#define ABSL_COMPARE_INLINE_BASECLASS_DECL(name) \ + ABSL_CONST_INIT static const T name + +#define ABSL_COMPARE_INLINE_SUBCLASS_DECL(type, name) + +#define ABSL_COMPARE_INLINE_INIT(type, name, init) \ + template <typename T> \ + const T compare_internal::type##_base<T>::name(init) + +#endif // __cpp_inline_variables + // These template base classes allow for defining the values of the constants // in the header file (for performance) without using inline variables (which // aren't available in C++11). template <typename T> struct weak_equality_base { - ABSL_CONST_INIT static const T equivalent; - ABSL_CONST_INIT static const T nonequivalent; + ABSL_COMPARE_INLINE_BASECLASS_DECL(equivalent); + ABSL_COMPARE_INLINE_BASECLASS_DECL(nonequivalent); }; -template <typename T> -const T weak_equality_base<T>::equivalent(eq::equivalent); -template <typename T> -const T weak_equality_base<T>::nonequivalent(eq::nonequivalent); template <typename T> struct strong_equality_base { - ABSL_CONST_INIT static const T equal; - ABSL_CONST_INIT static const T nonequal; - ABSL_CONST_INIT static const T equivalent; - ABSL_CONST_INIT static const T nonequivalent; + ABSL_COMPARE_INLINE_BASECLASS_DECL(equal); + ABSL_COMPARE_INLINE_BASECLASS_DECL(nonequal); + ABSL_COMPARE_INLINE_BASECLASS_DECL(equivalent); + ABSL_COMPARE_INLINE_BASECLASS_DECL(nonequivalent); }; -template <typename T> -const T strong_equality_base<T>::equal(eq::equal); -template <typename T> -const T strong_equality_base<T>::nonequal(eq::nonequal); -template <typename T> -const T strong_equality_base<T>::equivalent(eq::equivalent); -template <typename T> -const T strong_equality_base<T>::nonequivalent(eq::nonequivalent); template <typename T> struct partial_ordering_base { - ABSL_CONST_INIT static const T less; - ABSL_CONST_INIT static const T equivalent; - ABSL_CONST_INIT static const T greater; - ABSL_CONST_INIT static const T unordered; + ABSL_COMPARE_INLINE_BASECLASS_DECL(less); + ABSL_COMPARE_INLINE_BASECLASS_DECL(equivalent); + ABSL_COMPARE_INLINE_BASECLASS_DECL(greater); + ABSL_COMPARE_INLINE_BASECLASS_DECL(unordered); }; -template <typename T> -const T partial_ordering_base<T>::less(ord::less); -template <typename T> -const T partial_ordering_base<T>::equivalent(eq::equivalent); -template <typename T> -const T partial_ordering_base<T>::greater(ord::greater); -template <typename T> -const T partial_ordering_base<T>::unordered(ncmp::unordered); template <typename T> struct weak_ordering_base { - ABSL_CONST_INIT static const T less; - ABSL_CONST_INIT static const T equivalent; - ABSL_CONST_INIT static const T greater; + ABSL_COMPARE_INLINE_BASECLASS_DECL(less); + ABSL_COMPARE_INLINE_BASECLASS_DECL(equivalent); + ABSL_COMPARE_INLINE_BASECLASS_DECL(greater); }; -template <typename T> -const T weak_ordering_base<T>::less(ord::less); -template <typename T> -const T weak_ordering_base<T>::equivalent(eq::equivalent); -template <typename T> -const T weak_ordering_base<T>::greater(ord::greater); template <typename T> struct strong_ordering_base { - ABSL_CONST_INIT static const T less; - ABSL_CONST_INIT static const T equal; - ABSL_CONST_INIT static const T equivalent; - ABSL_CONST_INIT static const T greater; + ABSL_COMPARE_INLINE_BASECLASS_DECL(less); + ABSL_COMPARE_INLINE_BASECLASS_DECL(equal); + ABSL_COMPARE_INLINE_BASECLASS_DECL(equivalent); + ABSL_COMPARE_INLINE_BASECLASS_DECL(greater); }; -template <typename T> -const T strong_ordering_base<T>::less(ord::less); -template <typename T> -const T strong_ordering_base<T>::equal(eq::equal); -template <typename T> -const T strong_ordering_base<T>::equivalent(eq::equivalent); -template <typename T> -const T strong_ordering_base<T>::greater(ord::greater); } // namespace compare_internal @@ -162,6 +155,9 @@ class weak_equality friend struct compare_internal::weak_equality_base<weak_equality>; public: + ABSL_COMPARE_INLINE_SUBCLASS_DECL(weak_equality, equivalent); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(weak_equality, nonequivalent); + // Comparisons friend constexpr bool operator==( weak_equality v, compare_internal::OnlyLiteralZero<>) noexcept { @@ -183,6 +179,10 @@ class weak_equality private: compare_internal::value_type value_; }; +ABSL_COMPARE_INLINE_INIT(weak_equality, equivalent, + compare_internal::eq::equivalent); +ABSL_COMPARE_INLINE_INIT(weak_equality, nonequivalent, + compare_internal::eq::nonequivalent); class strong_equality : public compare_internal::strong_equality_base<strong_equality> { @@ -191,6 +191,11 @@ class strong_equality friend struct compare_internal::strong_equality_base<strong_equality>; public: + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_equality, equal); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_equality, nonequal); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_equality, equivalent); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_equality, nonequivalent); + // Conversion constexpr operator weak_equality() const noexcept { // NOLINT return value_ == 0 ? weak_equality::equivalent @@ -217,6 +222,13 @@ class strong_equality private: compare_internal::value_type value_; }; +ABSL_COMPARE_INLINE_INIT(strong_equality, equal, compare_internal::eq::equal); +ABSL_COMPARE_INLINE_INIT(strong_equality, nonequal, + compare_internal::eq::nonequal); +ABSL_COMPARE_INLINE_INIT(strong_equality, equivalent, + compare_internal::eq::equivalent); +ABSL_COMPARE_INLINE_INIT(strong_equality, nonequivalent, + compare_internal::eq::nonequivalent); class partial_ordering : public compare_internal::partial_ordering_base<partial_ordering> { @@ -234,6 +246,11 @@ class partial_ordering } public: + ABSL_COMPARE_INLINE_SUBCLASS_DECL(partial_ordering, less); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(partial_ordering, equivalent); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(partial_ordering, greater); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(partial_ordering, unordered); + // Conversion constexpr operator weak_equality() const noexcept { // NOLINT return value_ == 0 ? weak_equality::equivalent @@ -292,6 +309,13 @@ class partial_ordering private: compare_internal::value_type value_; }; +ABSL_COMPARE_INLINE_INIT(partial_ordering, less, compare_internal::ord::less); +ABSL_COMPARE_INLINE_INIT(partial_ordering, equivalent, + compare_internal::eq::equivalent); +ABSL_COMPARE_INLINE_INIT(partial_ordering, greater, + compare_internal::ord::greater); +ABSL_COMPARE_INLINE_INIT(partial_ordering, unordered, + compare_internal::ncmp::unordered); class weak_ordering : public compare_internal::weak_ordering_base<weak_ordering> { @@ -302,6 +326,10 @@ class weak_ordering friend struct compare_internal::weak_ordering_base<weak_ordering>; public: + ABSL_COMPARE_INLINE_SUBCLASS_DECL(weak_ordering, less); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(weak_ordering, equivalent); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(weak_ordering, greater); + // Conversions constexpr operator weak_equality() const noexcept { // NOLINT return value_ == 0 ? weak_equality::equivalent @@ -365,6 +393,11 @@ class weak_ordering private: compare_internal::value_type value_; }; +ABSL_COMPARE_INLINE_INIT(weak_ordering, less, compare_internal::ord::less); +ABSL_COMPARE_INLINE_INIT(weak_ordering, equivalent, + compare_internal::eq::equivalent); +ABSL_COMPARE_INLINE_INIT(weak_ordering, greater, + compare_internal::ord::greater); class strong_ordering : public compare_internal::strong_ordering_base<strong_ordering> { @@ -375,6 +408,11 @@ class strong_ordering friend struct compare_internal::strong_ordering_base<strong_ordering>; public: + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_ordering, less); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_ordering, equal); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_ordering, equivalent); + ABSL_COMPARE_INLINE_SUBCLASS_DECL(strong_ordering, greater); + // Conversions constexpr operator weak_equality() const noexcept { // NOLINT return value_ == 0 ? weak_equality::equivalent @@ -446,6 +484,16 @@ class strong_ordering private: compare_internal::value_type value_; }; +ABSL_COMPARE_INLINE_INIT(strong_ordering, less, compare_internal::ord::less); +ABSL_COMPARE_INLINE_INIT(strong_ordering, equal, compare_internal::eq::equal); +ABSL_COMPARE_INLINE_INIT(strong_ordering, equivalent, + compare_internal::eq::equivalent); +ABSL_COMPARE_INLINE_INIT(strong_ordering, greater, + compare_internal::ord::greater); + +#undef ABSL_COMPARE_INLINE_BASECLASS_DECL +#undef ABSL_COMPARE_INLINE_SUBCLASS_DECL +#undef ABSL_COMPARE_INLINE_INIT namespace compare_internal { // We also provide these comparator adapter functions for internal absl use. |