tmp/tmp08jw1gzy/{from.md → to.md}
RENAMED
|
@@ -1,38 +1,31 @@
|
|
| 1 |
#### Class `compare_three_way` <a id="comparisons.three.way">[[comparisons.three.way]]</a>
|
| 2 |
|
| 3 |
-
In this subclause, `BUILTIN-PTR-THREE-WAY(T, U)` for types `T` and `U`
|
| 4 |
-
is a boolean constant expression. `BUILTIN-PTR-THREE-WAY(T, U)` is
|
| 5 |
-
`true` if and only if `<=>` in the expression
|
| 6 |
-
|
| 7 |
-
``` cpp
|
| 8 |
-
declval<T>() <=> declval<U>()
|
| 9 |
-
```
|
| 10 |
-
|
| 11 |
-
resolves to a built-in operator comparing pointers.
|
| 12 |
-
|
| 13 |
``` cpp
|
|
|
|
| 14 |
struct compare_three_way {
|
| 15 |
template<class T, class U>
|
| 16 |
-
requires three_way_comparable_with<T, U> || BUILTIN-PTR-THREE-WAY(T, U)
|
| 17 |
constexpr auto operator()(T&& t, U&& u) const;
|
| 18 |
|
| 19 |
using is_transparent = unspecified;
|
| 20 |
};
|
|
|
|
| 21 |
```
|
| 22 |
|
| 23 |
``` cpp
|
| 24 |
template<class T, class U>
|
| 25 |
-
requires three_way_comparable_with<T, U> || BUILTIN-PTR-THREE-WAY(T, U)
|
| 26 |
constexpr auto operator()(T&& t, U&& u) const;
|
| 27 |
```
|
| 28 |
|
|
|
|
|
|
|
| 29 |
*Preconditions:* If the expression
|
| 30 |
`std::forward<T>(t) <=> std::forward<U>(u)` results in a call to a
|
| 31 |
built-in operator `<=>` comparing pointers of type `P`, the conversion
|
| 32 |
sequences from both `T` and `U` to `P` are
|
| 33 |
-
equality-preserving [[concepts.equality]]
|
|
|
|
| 34 |
|
| 35 |
*Effects:*
|
| 36 |
|
| 37 |
- If the expression `std::forward<T>(t) <=> std::forward<U>(u)` results
|
| 38 |
in a call to a built-in operator `<=>` comparing pointers of type `P`,
|
|
|
|
| 1 |
#### Class `compare_three_way` <a id="comparisons.three.way">[[comparisons.three.way]]</a>
|
| 2 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 3 |
``` cpp
|
| 4 |
+
namespace std {
|
| 5 |
struct compare_three_way {
|
| 6 |
template<class T, class U>
|
|
|
|
| 7 |
constexpr auto operator()(T&& t, U&& u) const;
|
| 8 |
|
| 9 |
using is_transparent = unspecified;
|
| 10 |
};
|
| 11 |
+
}
|
| 12 |
```
|
| 13 |
|
| 14 |
``` cpp
|
| 15 |
template<class T, class U>
|
|
|
|
| 16 |
constexpr auto operator()(T&& t, U&& u) const;
|
| 17 |
```
|
| 18 |
|
| 19 |
+
*Constraints:* `T` and `U` satisfy `three_way_comparable_with`.
|
| 20 |
+
|
| 21 |
*Preconditions:* If the expression
|
| 22 |
`std::forward<T>(t) <=> std::forward<U>(u)` results in a call to a
|
| 23 |
built-in operator `<=>` comparing pointers of type `P`, the conversion
|
| 24 |
sequences from both `T` and `U` to `P` are
|
| 25 |
+
equality-preserving [[concepts.equality]]; otherwise, `T` and `U` model
|
| 26 |
+
`three_way_comparable_with`.
|
| 27 |
|
| 28 |
*Effects:*
|
| 29 |
|
| 30 |
- If the expression `std::forward<T>(t) <=> std::forward<U>(u)` results
|
| 31 |
in a call to a built-in operator `<=>` comparing pointers of type `P`,
|