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[dcl.typedef]

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  ### The `typedef` specifier <a id="dcl.typedef">[[dcl.typedef]]</a>
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- Declarations containing the *decl-specifier* `typedef` declare
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- identifiers that can be used later for naming fundamental
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- [[basic.fundamental]] or compound [[basic.compound]] types. The
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- `typedef` specifier shall not be combined in a *decl-specifier-seq* with
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- any other kind of specifier except a *defining-type-specifier*, and it
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- shall not be used in the *decl-specifier-seq* of a
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- *parameter-declaration* [[dcl.fct]] nor in the *decl-specifier-seq* of a
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- *function-definition* [[dcl.fct.def]]. If a `typedef` specifier appears
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- in a declaration without a *declarator*, the program is ill-formed.
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  ``` bnf
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  typedef-name:
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  identifier
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  simple-template-id
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  ```
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- A name declared with the `typedef` specifier becomes a *typedef-name*. A
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- *typedef-name* names the type associated with the *identifier*
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- [[dcl.decl]] or *simple-template-id* [[temp.pre]]; a *typedef-name* is
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- thus a synonym for another type. A *typedef-name* does not introduce a
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- new type the way a class declaration [[class.name]] or enum declaration
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- [[dcl.enum]] does.
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  [*Example 1*:
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  After
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@@ -41,16 +39,16 @@ extern KLICKSP metricp;
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  are all correct declarations; the type of `distance` is `int` and that
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  of `metricp` is “pointer to `int`”.
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  — *end example*]
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- A *typedef-name* can also be introduced by an *alias-declaration*. The
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  *identifier* following the `using` keyword is not looked up; it becomes
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- a *typedef-name* and the optional *attribute-specifier-seq* following
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- the *identifier* appertains to that *typedef-name*. Such a
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- *typedef-name* has the same semantics as if it were introduced by the
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- `typedef` specifier. In particular, it does not define a new type.
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  [*Example 2*:
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  ``` cpp
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  using handler_t = void (*)(int);
@@ -65,11 +63,11 @@ using cell = P<cell*>; // error: cell not found[basic.scope.pdecl]
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  The *defining-type-specifier-seq* of the *defining-type-id* shall not
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  define a class or enumeration if the *alias-declaration* is the
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  *declaration* of a *template-declaration*.
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  A *simple-template-id* is only a *typedef-name* if its *template-name*
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- names an alias template or a template *template-parameter*.
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  [*Note 1*: A *simple-template-id* that names a class template
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  specialization is a *class-name* [[class.name]]. If a *typedef-name* is
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  used to identify the subject of an *elaborated-type-specifier*
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  [[dcl.type.elab]], a class definition [[class]], a constructor
 
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  ### The `typedef` specifier <a id="dcl.typedef">[[dcl.typedef]]</a>
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+ Declarations containing the *decl-specifier* `typedef` declare *type
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+ aliases*. The `typedef` specifier shall not be combined in a
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+ *decl-specifier-seq* with any other kind of specifier except a
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+ *defining-type-specifier*, and it shall not be used in the
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+ *decl-specifier-seq* of a *parameter-declaration* [[dcl.fct]] nor in the
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+ *decl-specifier-seq* of a *function-definition* [[dcl.fct.def]]. If a
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+ `typedef` specifier appears in a declaration without a *declarator*, the
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+ program is ill-formed.
 
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  ``` bnf
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  typedef-name:
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  identifier
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  simple-template-id
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  ```
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+ A name declared with the `typedef` specifier becomes a *typedef-name*.
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+ The underlying entity of the type alias is the type associated with the
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+ *identifier* [[dcl.decl]] or *simple-template-id* [[temp.pre]]. A
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+ *typedef-name* does not introduce a new type the way a class declaration
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+ [[class.name]] or enum declaration [[dcl.enum]] does.
 
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  [*Example 1*:
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  After
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  are all correct declarations; the type of `distance` is `int` and that
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  of `metricp` is “pointer to `int`”.
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  — *end example*]
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+ A type alias can also be declared by an *alias-declaration*. The
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  *identifier* following the `using` keyword is not looked up; it becomes
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+ the *typedef-name* of a type alias and the optional
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+ *attribute-specifier-seq* following the *identifier* appertains to that
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+ type alias. Such a type alias has the same semantics as if it were
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+ introduced by the `typedef` specifier.
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  [*Example 2*:
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  ``` cpp
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  using handler_t = void (*)(int);
 
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  The *defining-type-specifier-seq* of the *defining-type-id* shall not
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  define a class or enumeration if the *alias-declaration* is the
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  *declaration* of a *template-declaration*.
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  A *simple-template-id* is only a *typedef-name* if its *template-name*
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+ names an alias template or a type template template parameter.
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  [*Note 1*: A *simple-template-id* that names a class template
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  specialization is a *class-name* [[class.name]]. If a *typedef-name* is
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  used to identify the subject of an *elaborated-type-specifier*
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  [[dcl.type.elab]], a class definition [[class]], a constructor