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std::is_trivial(3)	      C++ Standard Libary	    std::is_trivial(3)

NAME
       std::is_trivial - std::is_trivial

Synopsis
	  Defined in header <type_traits>
	  template< class T >		   (since C++11)
	  struct is_trivial;

	  If  T	is a trivial type, provides the	member constant	value equal to
       true. For any
	  other	type, value is false.

	  The behavior is undefined if std::remove_all_extents_t<T> is an  in-
       complete	type and
	  not (possibly	cv-qualified) void.

	  The behavior of a program that adds specializations for is_trivial
	  or is_trivial_v
	  (since C++17)	is undefined.

Template parameters
	  T - a	type to	check

	 Helper	variable template

	  template<  class  T >						(since
       C++17)
	  inline constexpr bool	is_trivial_v = is_trivial<T>::value;

       Inherited from std::integral_constant

Member constants
	  value	   true	if T is	a trivial type , false otherwise
	  [static] (public static member constant)

Member functions
	  operator bool	converts the object to bool, returns value
			(public	member function)
	  operator()	returns	value
	  (C++14)	(public	member function)

Member types
	  Type	     Definition
	  value_type bool
	  type	     std::integral_constant<bool, value>

Possible implementation
	  template<class T>
	  struct is_trivial : std::integral_constant<
	      bool,
	      std::is_trivially_copyable<T>::value &&
	      std::is_trivially_default_constructible<T>::value
	  > {};

Example
       // Run this code

	#include <iostream>
	#include <type_traits>

	struct A
	{
	    int	m;
	};

	struct B
	{
	    B()	{}
	};

	int main()
	{
	    std::cout << std::boolalpha;
	    std::cout << std::is_trivial<A>::value << '\n';
	    std::cout << std::is_trivial<B>::value << '\n';
	}

Output:
	true
	false

See also
	  is_trivially_copyable		     checks if	a  type	 is  trivially
       copyable
	  (C++11)			     (class template)
	  is_default_constructible
	  is_trivially_default_constructible
	  is_nothrow_default_constructible    checks  if  a type has a default
       constructor
	  (C++11)			     (class template)
	  (C++11)
	  (C++11)

http://cppreference.com		  2022.07.31		    std::is_trivial(3)

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