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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 errors
     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 mes-
     sage
		      (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  exceptions,
     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 construct
     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 ob-
     ject 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  as-
     signment. 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 de-
     fined as long
	as the explanatory strings obtained by what() are the same for the orig-
     inal 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		 Correct
     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,Alloca-
     tor>)

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