std::meta::is_volatile

 

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

Let T be std::meta::type_of(r) if has-type(r) is true. Otherwise, let T be std::meta::dealias(r).

Returns: true if T represents a volatile (or const volatile) type, or a volatile-qualified function type. Otherwise, false.

Parameters

r

-

a reflection value

Return value

true if T represents a volatile type, or a volatile-qualified function type. Otherwise, false.

Example

Run this code

#include <meta>

int a;
volatile int b;
static_assert(!is_volatile(^^a));
static_assert( is_volatile(^^b));

void foo();

struct S
{
    auto bar() const volatile noexcept -> void;
};
static_assert(!is_volatile(^^foo));
static_assert( is_volatile(^^S::bar));

int main() {}

See also

is_volatile (C++11)	checks if a type is volatile-qualified (class template)
add_cvadd_constadd_volatile (C++26)(C++26)(C++26)	adds const and/or volatile specifiers to reflected type (function)
add_cvadd_constadd_volatile (C++11)(C++11)(C++11)	adds const and/or volatile specifiers to the given type (class template)
remove_cvremove_constremove_volatile (C++26)(C++26)(C++26)	removes const and/or volatile specifiers from reflected type (function)
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11)	removes const and/or volatile specifiers from the given type (class template)