tmp/tmp8tl8dt_8/{from.md → to.md}
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| 1 |
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#### Type splicing <a id="dcl.type.splice">[[dcl.type.splice]]</a>
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``` bnf
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splice-type-specifier:
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typenameₒₚₜ splice-specifier
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typenameₒₚₜ splice-specialization-specifier
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```
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A *splice-specifier* or *splice-specialization-specifier* immediately
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followed by `::` is never interpreted as part of a
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*splice-type-specifier*. A *splice-specifier* or
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*splice-specialization-specifier* not preceded by `typename` is only
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interpreted as a *splice-type-specifier* within a type-only context
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[[temp.res.general]].
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[*Example 1*:
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``` cpp
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template<std::meta::info R> void tfn() {
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typename [:R:]::type m; // OK, typename applies to the qualified name
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}
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struct S { using type = int; };
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void fn() {
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[:^^S::type:] *var; // error: [:^^ S::type:] is an expression
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typename [:^^S::type:] *var; // OK, declares variable with type int*
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}
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using alias = [:^^S::type:]; // OK, type-only context
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```
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— *end example*]
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For a *splice-type-specifier* of the form `typename`ₒₚₜ
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*splice-specifier*, the *splice-specifier* shall designate a type, a
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class template, or an alias template. The *splice-type-specifier*
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designates the same entity as the *splice-specifier*.
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For a *splice-type-specifier* of the form `typename`ₒₚₜ
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*splice-specialization-specifier*, the *splice-specifier* of the
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*splice-specialization-specifier* shall designate a template `T` that is
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either a class template or an alias template. The
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*splice-type-specifier* designates the specialization of `T`
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corresponding to the template argument list of the
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*splice-specialization-specifier*.
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