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

NAME
       std::make_any - std::make_any

Synopsis
	  template<	   class	T,	  class...	  Args	     >
       (1) (since C++17)
	  std::any make_any( Args&&... args );
	  template<    class	T,    class	U,     class...	    Args     >
       (2) (since C++17)
	  std::any make_any( std::initializer_list<U> il, Args&&... args );

	  Constructs an	any object containing an object	of type	T, passing the
       provided
	  arguments to T's constructor.

	  1) Equivalent	to return std::any(std::in_place_type<T>,
	  std::forward<Args>(args)...);
	  2) Equivalent	to return std::any(std::in_place_type<T>, il,
	  std::forward<Args>(args)...);

Example
       // Run this code

	#include <any>
	#include <complex>
	#include <functional>
	#include <iostream>
	#include <string>

	int main()
	{
	    auto a0 = std::make_any<std::string>("Hello, std::any!\n");
	    auto a1 = std::make_any<std::complex<double>>(0.1, 2.3);

	    std::cout << std::any_cast<std::string&>(a0);
	    std::cout << std::any_cast<std::complex<double>&>(a1) << '\n';

	    using lambda = std::function<void(void)>;

	    // Put a lambda into std::any. Attempt #1 (failed).
	    std::any a2	= [] { std::cout << "Lambda #1.\n"; };
	    std::cout << "a2.type() = \"" << a2.type().name() << "\"\n";

	    // any_cast	casts to <void(void)> but actual type is not
	    // a std::function..., but ~ main::{lambda()#1}, and it is
	    // unique for each lambda. So, this	throws...
	    try	{
		std::any_cast<lambda>(a2)();
	    }
	    catch (std::bad_any_cast const& ex)	{
		std::cout << ex.what() << '\n';
	    }

	    // Put a lambda into std::any. Attempt #2 (successful).
	    auto  a3 = std::make_any<lambda>([]	{ std::cout << "Lambda #2.\n";
       });
	    std::cout << "a3.type() = \"" << a3.type().name() << "\"\n";
	    std::any_cast<lambda>(a3)();
	}

Possible output:
	Hello, std::any!
	(0.1,2.3)
	a2.type() = "Z4mainEUlvE_"
	bad any_cast
	a3.type() = "St8functionIFvvEE"
	Lambda #2.

See also
	  constructor	constructs an any object
			(public	member function)
	  any_cast	type-safe access to the	contained object
	  (C++17)	(function template)

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

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