std::chrono::ambiguous_local_time

 

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Defined in header <chrono>
class ambiguous_local_time;		(since C++20)

Defines a type of object to be thrown as exception to report that an attempt was made to convert an ambiguous std::chrono::local_time to a std::chrono::sys_time without specifying a std::chrono::choose (such as choose::earliest or choose::latest).

This exception is thrown by std::chrono::time_zone::to_sys and functions that call it (such as the constructors of std::chrono::zoned_time that take a std::chrono::local_time).

Inheritance diagram

Member functions

(constructor)	constructs the exception object (public member function)
operator=	replaces the exception object (public member function)
what	returns the explanatory string (public member function)

std::chrono::ambiguous_local_time::ambiguous_local_time

template< class Duration > ambiguous_local_time( const std::chrono::local_time<Duration>& tp,                       const std::chrono::local_info& i );	(1)	(since C++20)
ambiguous_local_time( const ambiguous_local_time& other ) noexcept;	(2)	(since C++20)

Constructs the exception object.

1) The explanatory string returned by what() is equivalent to that produced by os.str() after the following code:

std::ostringstream os;
os << tp << " is ambiguous.  It could be\n"
   << tp << ' ' << i.first.abbrev << " == "
   << tp - i.first.offset << " UTC or\n"
   << tp << ' ' << i.second.abbrev  << " == "
   << tp - i.second.offset  << " UTC";

The behavior is undefined if i.result != std::chrono::local_info::ambiguous.

2) Copy constructor. If *this and other both have dynamic type std::chrono::ambiguous_local_time then std::strcmp(what(), other.what()) == 0.

Parameters

tp	-	the time point for which conversion was attempted
i	-	a std::chrono::local_info describing the result of the conversion attempt
other	-	another ambiguous_local_time to copy

Exceptions

May throw std::bad_alloc

Notes

Because copying a standard library class derived from std::exception is not permitted to throw exceptions, this message is typically stored internally as a separately-allocated reference-counted string.

std::chrono::ambiguous_locale_time::operator=

ambiguous_locale_time& operator=( const ambiguous_locale_time& other ) noexcept;		(since C++20)

Assigns the contents with those of other. If *this and other both have dynamic type std::chrono::ambiguous_locale_time then std::strcmp(what(), other.what()) == 0 after assignment.

Parameters

other

-

another exception object to assign with

Return value

*this

std::chrono::ambiguous_locale_time::what

virtual const char* what() const noexcept;		(since C++20)

Returns the explanatory string.

Parameters

(none)

Return value

Pointer to a null-terminated string with explanatory information. The string is suitable for conversion and display as a std::wstring. The pointer is guaranteed to be valid at least until the exception object from which it is obtained is destroyed, or until a non-const member function (e.g. copy assignment operator) on the exception object is called.

Notes

Implementations are allowed but not required to override what().

Inherited from std::runtime_error

Inherited from std::exception

Member functions

(destructor) [virtual]	destroys the exception object (virtual public member function of std::exception)
what [virtual]	returns an explanatory string (virtual public member function of std::exception)

See also

nonexistent_local_time (C++20)

exception thrown to report that a local time is nonexistent (class)