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Difference between revisions of "cpp/keyword/typename"

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< cpp‎ | keyword
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{{cpp/keyword/title|typename}}
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{{cpp/keyword/title|{{tt|typename}}}}
 
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===Usage===
 
===Usage===
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* In the template parameter list of a [[cpp/language/templates|template declaration]], {{c|typename}} can be used as an alternative to {{lt|cpp/keyword/class}} to declare {{lsd|cpp/language/template parameters#Type template parameter}}s{{rev inl|since=c++17| and template template parameters}}.
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* Inside a declaration or a definition of a template, {{c|typename}} can be used to declare that a [[cpp/language/dependent name|dependent qualified name]] is a type.
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* {{c|typename}} can be used before a non-dependent qualified type name. It has no effect in this case.
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{{rrev|since=c++20|
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* Inside a [[cpp/language/constraints|requirements]] for type requirements
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}}
  
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* In the template parameter list of a [[cpp/language/templates | template declaration]], {{c|typename}} can be used as an alternative to [[cpp/keyword/class | class]] to declare [[cpp/language/template_parameters#Type template parameter|type template parameters]] {{rev inl|since=c++17|and template template parameters}}.
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===See also===
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* Inside a declaration or a definition of a template, {{c|typename}} can be used to declare that a [[cpp/language/dependent_name|dependent qualified name]] is a type.
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* {{rlpt|class}}
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* {{rev inl|until=c++11|Inside a declaration or a definition of a template,}} {{c|typename}} can be used before a non-dependent qualified type name. It has no effect in this case.
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* {{rlpt|template}}
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* Inside a [[cpp/language/constraints | requirements]] for type requirements {{mark since c++20}}
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{{rrev|since=c++20|
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* {{rlpt|concept}}, {{rlpt|requires}}
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}}
  
 
{{langlinks|de|es|fr|it|ja|pt|ru|zh}}
 
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Latest revision as of 04:44, 14 August 2024

 
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[edit] Usage

  • In the template parameter list of a template declaration, typename can be used as an alternative to class to declare type template parameters and template template parameters(since C++17).
  • Inside a declaration or a definition of a template, typename can be used to declare that a dependent qualified name is a type.
  • typename can be used before a non-dependent qualified type name. It has no effect in this case.
(since C++20)

[edit] See also

(since C++20)
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