tmp/tmps_ssxpcy/{from.md → to.md}
RENAMED
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@@ -20,28 +20,30 @@ overload resolution ([[over.match]]) on a candidate set that includes:
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- the two `swap` function templates defined in `<utility>` (
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[[utility]]) and
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- the lookup set produced by argument-dependent lookup (
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[[basic.lookup.argdep]]).
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If `T` and `U` are both fundamental types or arrays of
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and the declarations from the header `<utility>` are
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overall lookup set described above is equivalent to that
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qualified name lookup applied to the expression `std::swap(t, u)`
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`std::swap(u, t)` as appropriate.
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It is unspecified whether a library component that has a
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requirement includes the header `<utility>` to ensure an
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evaluation context.
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An rvalue or lvalue `t` is *swappable* if and only if `t` is swappable
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with any rvalue or lvalue, respectively, of type `T`.
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A type `X` satisfying any of the iterator requirements (
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[[iterator.requirements]]) satisfies the requirements of
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`ValueSwappable` if, for any dereferenceable object `x` of type `X`,
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`*x` is swappable.
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User code can ensure that the evaluation of `swap` calls is performed in
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an appropriate context under the various conditions as follows:
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``` cpp
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#include <utility>
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@@ -54,11 +56,11 @@ void value_swap(T&& t, U&& u) {
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// for rvalues and lvalues
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}
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// Requires: lvalues of T shall be swappable.
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template <class T>
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-
void lv_swap(T& t1 T& t2) {
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using std::swap;
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swap(t1, t2); // OK: uses swappable conditions for
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} // lvalues of type T
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namespace N {
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@@ -82,5 +84,7 @@ int main() {
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value_swap(a1, proxy(a2));
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assert(a1.m == -5 && a2.m == 5);
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}
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```
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- the two `swap` function templates defined in `<utility>` (
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[[utility]]) and
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- the lookup set produced by argument-dependent lookup (
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[[basic.lookup.argdep]]).
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+
[*Note 1*: If `T` and `U` are both fundamental types or arrays of
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fundamental types and the declarations from the header `<utility>` are
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in scope, the overall lookup set described above is equivalent to that
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of the qualified name lookup applied to the expression `std::swap(t, u)`
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or `std::swap(u, t)` as appropriate. — *end note*]
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[*Note 2*: It is unspecified whether a library component that has a
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swappable requirement includes the header `<utility>` to ensure an
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appropriate evaluation context. — *end note*]
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An rvalue or lvalue `t` is *swappable* if and only if `t` is swappable
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with any rvalue or lvalue, respectively, of type `T`.
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A type `X` satisfying any of the iterator requirements (
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[[iterator.requirements]]) satisfies the requirements of
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`ValueSwappable` if, for any dereferenceable object `x` of type `X`,
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`*x` is swappable.
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[*Example 1*:
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User code can ensure that the evaluation of `swap` calls is performed in
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an appropriate context under the various conditions as follows:
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``` cpp
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#include <utility>
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// for rvalues and lvalues
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}
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// Requires: lvalues of T shall be swappable.
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template <class T>
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void lv_swap(T& t1, T& t2) {
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using std::swap;
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swap(t1, t2); // OK: uses swappable conditions for
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} // lvalues of type T
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namespace N {
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value_swap(a1, proxy(a2));
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assert(a1.m == -5 && a2.m == 5);
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}
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```
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— *end example*]
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