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

NAME
       std::length_error - std::length_error

Synopsis
	  Defined in header <stdexcept>
	  class	length_error;

	  Defines  a  type of object to	be thrown as exception.	It reports er-
       rors that result
	  from attempts	to exceed implementation  defined  length  limits  for
       some object.

	  This	exception  is  thrown by member	functions of std::basic_string
       and
	  std::vector::reserve.

	  std-length error-inheritance.svg

					  Inheritance diagram

Member functions
	  constructor	constructs a new length_error object  with  the	 given
       message
			(public	member function)
	  operator=	replaces the length_error object
			(public	member function)

       std::length_error::length_error

	  length_error(	const std::string& what_arg ); (1)
	  length_error(	const char* what_arg );	       (2)
	  length_error(	 const	length_error&  other  );   (3) (noexcept since
       C++11)

	  1) Constructs	the exception  object  with  what_arg  as  explanatory
       string. After
	  construction,	std::strcmp(what(), what_arg.c_str()) == 0.
	  2)  Constructs  the  exception  object  with what_arg	as explanatory
       string. After
	  construction,	std::strcmp(what(), what_arg) == 0.
	  3) Copy constructor. If *this	 and  other  both  have	 dynamic  type
       std::length_error
	  then	std::strcmp(what(),  other.what())  ==	0. No exception	can be
       thrown from the
	  copy constructor.

Parameters
	  what_arg - explanatory string
	  other	   - another exception object to copy

Exceptions
	  1,2) May throw std::bad_alloc.

Notes
	  Because copying std::length_error is not permitted to	 throw	excep-
       tions, this message
	  is  typically	stored internally as a separately-allocated reference-
       counted string.
	  This is also why there is no constructor  taking  std::string&&:  it
       would have to copy
	  the content anyway.

	  Before the resolution	of LWG issue 254, the non-copy constructor can
       only accept
	  std::string.	It makes dynamic allocation mandatory in order to con-
       struct a
	  std::string object.

	  After	the resolution of LWG issue 471, a derived standard  exception
       class must have
	  a publicly accessible	copy constructor. It can be implicitly defined
       as long as the
	  explanatory strings obtained by what() are the same for the original
       object and the
	  copied object.

       std::length_error::operator=

	  length_error&	 operator=(  const  length_error&  other );  (noexcept
       since C++11)

	  Assigns the contents with those of other. If *this  and  other  both
       have dynamic type
	  std::length_error  then std::strcmp(what(), other.what()) == 0 after
       assignment. No
	  exception can	be thrown from the copy	assignment operator.

Parameters
	  other	- another exception object to assign with

Return value
	  *this

Notes
	  After	the resolution of LWG issue 471, a derived standard  exception
       class must have
	  a publicly accessible	copy assignment	operator. It can be implicitly
       defined as long
	  as  the  explanatory strings obtained	by what() are the same for the
       original	object
	  and the copied object.

       Inherited from std::logic_error

       Inherited from std::exception

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

	  Defect reports

	  The following	behavior-changing defect reports were applied retroac-
       tively to
	  previously published C++ standards.

	    DR	  Applied to	     Behavior as published		  Cor-
       rect behavior
	  LWG 254 C++98	     the constructor accepting const char*  added
			     was missing
			     the  explanatory  strings of	      they are
       the same	as that
	  LWG 471 C++98	     std::length_error's		    of the
			     copies were  implementation-defined      original
       std::length_error
								    object

See also
	  resize changes the number of characters stored
		 (public member	function of std::basic_string<CharT,Traits,Al-
       locator>)

http://cppreference.com		  2024.06.10		  std::length_error(3)

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