std::meta::template_of

 

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Member accessibility queries is_accessible has_inaccessible_nonstatic_   data_members has_inaccessible_bases has_inaccessible_subobjects      Scope identification current_function current_class current_namespace Reflection member queries members_of bases_of static_data_members_of nonstatic_data_members_of subobjects_of enumerators_of Annotation reflection annotations_of annotations_of_with_type Value extraction extract Reflection substitution reflection_range can_substitute substitute Expression result reflection reflect_constant reflect_object reflect_function Class definition generation data_member_options data_member_spec is_data_member_spec define_aggregate

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

Given a reflection r that represents an entity instantiated from a function template, variable template, class template, or alias template, returns a reflection of the template.

Parameters

r

-

a reflection value

Return value

The template from which the function, variable, class, or type alias represented by r is instantiated.

Exceptions

Throws std::meta::exception unless std::meta::has_template_arguments(r) is true (i.e. r represents an entity instantiated from a template).

Example

Run this code

#include <meta>
#include <string>
#include <vector>

static_assert(template_of(^^std::vector<int>) == ^^std::vector);
static_assert(!has_template_arguments(^^std::string));
static_assert(template_of(std::meta::dealias(^^std::string)) == ^^std::basic_string);

int main() {}

See also

Template:cpp/meta/dsc is template

has_template_arguments (C++26)

checks if reflected entity is produced by substituting template arguments into a template (function)