std::meta::type_of

 

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Defined in header <meta>
consteval std::meta::info type_of( std::meta::info r );		(since C++26)

See More

Returns a reflection representing the type of what r represents.

Formally:

• If r represents a function parameter (see std::meta::parameters_of), returns a reflection of the corresponding type in the parameter-type-list of the function.
• If r represents a value, object, variable, function, non-static data member, or unnamed bit-field, returns a reflection of the type of what r represents.
• If r represents an annotation, returns std::meta::type_of(std::meta::constant_of(r)).
• If r represents an enumerator of an enumeration type E :

• if type_of is called after E 's definition, returns a reflection of E ;
• otherwise (type_of is called within E 's definition), returns a reflection of an integer type (which is the type of the enumerator within the enumeration definition).

• If r represents a direct base class relationship (i.e. an element of std::meta::bases_of(x, ctx)), returns a reflection of the base class in the relationship.
• If r represents a data member description (i.e. a value returned by std::meta::data_member_spec), returns a reflection of the type in the description.

Parameters

r

-

a reflection of something that has a type

Return value

The type of what r represents.

Exceptions

Throws std::meta::exception unless what r represents has a type. That is, r must represent one of:

• value
• annotation
• object
• variable
• function whose type does not contain an undeduced placeholder type and that is not a constructor or destructor
• enumerator
• non-static data member
• unnamed bit-field
• direct base class relationship
• data member description
• function parameter

Example

See also