tmp/tmpxgys2n42/{from.md → to.md}
RENAMED
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@@ -1,7 +1,10 @@
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#### Other transformations <a id="meta.trans.other">[[meta.trans.other]]</a>
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[*Note 1*: The compilation of the expression can result in side effects
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such as the instantiation of class template specializations and function
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template specializations, the generation of implicitly-defined
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functions, and so on. Such side effects are not in the “immediate
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context” and can result in the program being ill-formed. — *end note*]
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@@ -42,13 +45,13 @@ Given types `A` and `B`, let `X` be `remove_reference_t<A>`, let `Y` be
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- Otherwise, `COMMON-REF(A, B)` is ill-formed.
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If any of the types computed above is ill-formed, then
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`COMMON-REF(A, B)` is ill-formed.
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-
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-
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-
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- If `sizeof...(T)` is zero, there shall be no member `type`.
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- If `sizeof...(T)` is one, let `T0` denote the sole type constituting
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the pack `T`. The member *typedef-name* `type` shall denote the same
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type, if any, as `common_type_t<T0, T0>`; otherwise there shall be no
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@@ -79,15 +82,14 @@ as follows:
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constituting `T`. Let `C` denote the same type, if any, as
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`common_type_t<T1, T2>`. If there is such a type `C`, the member
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*typedef-name* `type` shall denote the same type, if any, as
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`common_type_t<C, R...>`. Otherwise, there shall be no member `type`.
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-
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-
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-
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`is_same_v<
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`true`.
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[*Note 3*: Such specializations are needed when only explicit
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conversions are desired between the template arguments. — *end note*]
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Such a specialization need not have a member named `type`, but if it
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@@ -95,12 +97,12 @@ does, the *qualified-id* `common_type<T1, T2>::type` shall denote a
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cv-unqualified non-reference type to which each of the types `T1` and
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`T2` is explicitly convertible. Moreover, `common_type_t<T1, T2>` shall
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denote the same type, if any, as does `common_type_t<T2, T1>`. No
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diagnostic is required for a violation of this Note’s rules.
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-
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-
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follows:
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- If `sizeof...(T)` is zero, there shall be no member `type`.
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- Otherwise, if `sizeof...(T)` is one, let `T0` denote the sole type in
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the pack `T`. The member typedef `type` shall denote the same type as
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@@ -126,12 +128,12 @@ follows:
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`common_reference_t<T1, T2>`. Then:
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- If there is such a type `C`, the member typedef `type` shall denote
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the same type, if any, as `common_reference_t<C, Rest...>`.
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- Otherwise, there shall be no member `type`.
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-
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-
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`basic_common_reference<T, U, TQual, UQual>` for types `T` and `U` such
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that `is_same_v<T, decay_t<T>>` and `is_same_v<U, decay_t<U>>` are each
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`true`.
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[*Note 4*: Such specializations can be used to influence the result of
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#### Other transformations <a id="meta.trans.other">[[meta.trans.other]]</a>
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+
The templates specified in [[meta.trans.other]] perform other
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modifications of a type.
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+
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[*Note 1*: The compilation of the expression can result in side effects
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such as the instantiation of class template specializations and function
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template specializations, the generation of implicitly-defined
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functions, and so on. Such side effects are not in the “immediate
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context” and can result in the program being ill-formed. — *end note*]
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- Otherwise, `COMMON-REF(A, B)` is ill-formed.
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If any of the types computed above is ill-formed, then
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`COMMON-REF(A, B)` is ill-formed.
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+
For the `common_type` trait applied to a template parameter pack `T` of
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types, the member `type` shall be either defined or not present as
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follows:
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- If `sizeof...(T)` is zero, there shall be no member `type`.
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- If `sizeof...(T)` is one, let `T0` denote the sole type constituting
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the pack `T`. The member *typedef-name* `type` shall denote the same
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type, if any, as `common_type_t<T0, T0>`; otherwise there shall be no
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constituting `T`. Let `C` denote the same type, if any, as
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`common_type_t<T1, T2>`. If there is such a type `C`, the member
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*typedef-name* `type` shall denote the same type, if any, as
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`common_type_t<C, R...>`. Otherwise, there shall be no member `type`.
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Notwithstanding the provisions of [[meta.rqmts]], and pursuant to
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[[namespace.std]], a program may specialize `common_type<T1, T2>` for
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types `T1` and `T2` such that `is_same_v<T1, decay_t<T1>>` and
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`is_same_v<T2, decay_t<T2>>` are each `true`.
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[*Note 3*: Such specializations are needed when only explicit
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conversions are desired between the template arguments. — *end note*]
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Such a specialization need not have a member named `type`, but if it
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cv-unqualified non-reference type to which each of the types `T1` and
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`T2` is explicitly convertible. Moreover, `common_type_t<T1, T2>` shall
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denote the same type, if any, as does `common_type_t<T2, T1>`. No
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diagnostic is required for a violation of this Note’s rules.
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+
For the `common_reference` trait applied to a parameter pack `T` of
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types, the member `type` shall be either defined or not present as
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follows:
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- If `sizeof...(T)` is zero, there shall be no member `type`.
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- Otherwise, if `sizeof...(T)` is one, let `T0` denote the sole type in
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the pack `T`. The member typedef `type` shall denote the same type as
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`common_reference_t<T1, T2>`. Then:
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- If there is such a type `C`, the member typedef `type` shall denote
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the same type, if any, as `common_reference_t<C, Rest...>`.
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- Otherwise, there shall be no member `type`.
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Notwithstanding the provisions of [[meta.rqmts]], and pursuant to
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[[namespace.std]], a program may partially specialize
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`basic_common_reference<T, U, TQual, UQual>` for types `T` and `U` such
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that `is_same_v<T, decay_t<T>>` and `is_same_v<U, decay_t<U>>` are each
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`true`.
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[*Note 4*: Such specializations can be used to influence the result of
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