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std::chrono::zoned_time(3)     C++ Standard Libary    std::chrono::zoned_time(3)

NAME
     std::chrono::zoned_time - std::chrono::zoned_time

Synopsis
	Defined in header <chrono>
	template<

	    class						       Duration,
     (since C++20)
	    class TimeZonePtr = const std::chrono::time_zone*

	> class zoned_time;
	using  zoned_seconds  =   std::chrono::zoned_time<std::chrono::seconds>;
     (since C++20)

	The class zoned_time represents a logical pairing of a time zone and a
	std::chrono::time_point whose resolution is Duration.

	An invariant of zoned_time is that it always refers to a valid time zone
     and
	represents  an	existing  and  unambiguous time point in that time zone.
     Consistent with
	this invariant, zoned_time has no move constructor  or	move  assignment
     operator;
	attempts to move a zoned_time will perform a copy.

	The program is ill-formed if Duration is not a specialization of
	std::chrono::duration.

	The template parameter TimeZonePtr allows users to supply their own time
     zone
	pointer types and further customize the behavior of zoned_time via
	std::chrono::zoned_traits.  Custom  time zone types need not support all
     the
	operations supported by std::chrono::time_zone, only those used  by  the
     functions
	actually called on the zoned_time.

	TimeZonePtr  must  be  MoveConstructible. Move-only TimeZonePtrs are al-
     lowed but
	difficult to use, as the zoned_time will be immovable and it is not pos-
     sible to
	access the stored TimeZonePtr.

Member types
	Member type Definition
	duration    std::common_type_t<Duration, std::chrono::seconds>

Member functions
	constructor	    constructs a zoned_time
			    (public member function)
	operator=	    assigns value to a zoned_time
			    (public member function)
	get_time_zone	    obtains a copy of the time zone pointer
			    (public member function)
	operator local_time obtains the stored time point as a local_time
	get_local_time	    (public member function)
	operator sys_time   obtains the stored time point as a sys_time
	get_sys_time	    (public member function)
	get_info	    obtain information about the time zone at the stored
     time point
			    (public member function)

Non-member functions
	operator== compares two zoned_time values
	(C++20)    (function template)
	operator<< outputs a zoned_time into a stream
	(C++20)    (function template)

Helper classes
	std::formatter<std::chrono::zoned_time>    formatting	 support     for
     zoned_time
	(C++20) 				(class template specialization)
	std::hash<std::chrono::zoned_time>	      hash	support      for
     std::chrono::zoned_time
	(C++26) 				(class template specialization)

	Deduction guides

Example
     // Run this code

      #include <algorithm>
      #include <chrono>
      #include <iomanip>
      #include <iostream>
      #include <stdexcept>
      #include <string_view>

      int main()
      {
	  constexpr std::string_view locations[] =
	  {
	      "Africa/Casablanca",   "America/Argentina/Buenos_Aires",
	      "America/Barbados",    "America/Indiana/Petersburg",
	      "America/Tarasco_Bar", "Antarctica/Casey",
	      "Antarctica/Vostok",   "Asia/Magadan",
	      "Asia/Manila",	     "Asia/Shanghai",
	      "Asia/Tokyo",	     "Atlantic/Bermuda",
	      "Australia/Darwin",    "Europe/Isle_of_Man",
	      "Europe/Laputa",	     "Indian/Christmas",
	      "Indian/Cocos",	     "Pacific/Galapagos",
	  };

	  constexpr auto width = std::ranges::max_element(locations, {},
	      [](const auto& s){ return s.length(); })->length();

	  for (const auto location : locations)
	      try
	      {
		  // may throw if 'location' is not in the time zone database
		  const std::chrono::zoned_time  zt{location,  std::chrono::sys-
     tem_clock::now()};
		  std::cout << std::setw(width) << location << " - Zoned Time: "
     << zt << '\n';
	      }
	      catch (std::runtime_error& ex)
	      {
		  std::cout << "Error: " << ex.what() << '\n';
	      }
      }

Possible output:
		   Africa/Casablanca - Zoned Time: 2023-06-29 20:58:34.697449319
     +01
      America/Argentina/Buenos_Aires - Zoned Time: 2023-06-29 16:58:34.709957354
     -03
		    America/Barbados - Zoned Time: 2023-06-29 15:58:34.709977888
     AST
	  America/Indiana/Petersburg - Zoned Time: 2023-06-29 15:58:34.709998072
     EDT
      Error: tzdb: cannot locate zone: America/Tarasco_Bar
		    Antarctica/Casey - Zoned Time: 2023-06-30 06:58:34.710093685
     +11
		   Antarctica/Vostok - Zoned Time: 2023-06-30 01:58:34.710107932
     +06
			Asia/Magadan - Zoned Time: 2023-06-30 06:58:34.710121831
     +11
			 Asia/Manila - Zoned Time: 2023-06-30 03:58:34.710134751
     PST
		       Asia/Shanghai - Zoned Time: 2023-06-30 03:58:34.710153259
     CST
			  Asia/Tokyo - Zoned Time: 2023-06-30 04:58:34.710172815
     JST
		    Atlantic/Bermuda - Zoned Time: 2023-06-29 16:58:34.710191043
     ADT
		    Australia/Darwin - Zoned Time: 2023-06-30 05:28:34.710236720
     ACST
		  Europe/Isle_of_Man - Zoned Time: 2023-06-29 20:58:34.710256834
     BST
      Error: tzdb: cannot locate zone: Europe/Laputa
		    Indian/Christmas - Zoned Time: 2023-06-30 02:58:34.710360409
     +07
			Indian/Cocos - Zoned Time: 2023-06-30 02:28:34.710377520
     +0630
		   Pacific/Galapagos - Zoned Time: 2023-06-29 13:58:34.710389952
     -06

See also
	time_zone represents a time zone
	(C++20)   (class)

http://cppreference.com 	   2024.06.10	      std::chrono::zoned_time(3)
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