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

NAME
     std::bad_alloc - std::bad_alloc

Synopsis
	Defined in header <new>
	class bad_alloc;

	std::bad_alloc is the type of the object thrown as exceptions by the al-
     location
	functions to report failure to allocate storage.

	std-bad alloc-inheritance.svg

					Inheritance diagram

Member functions
	constructor   constructs a new bad_alloc object
		      (public member function)
	operator=     replaces the bad_alloc object
		      (public member function)
	what	      returns the explanatory string
		      (public member function)

     std::bad_alloc::bad_alloc

	bad_alloc() throw();				      (until C++11)
	bad_alloc() noexcept;			      (1)     (since C++11)
	bad_alloc( const bad_alloc& other ) throw();	  (2)		    (un-
     til C++11)
	bad_alloc(	 const	     bad_alloc&      other	)      noexcept;
     (since C++11)

	Constructs a new bad_alloc object with an  implementation-defined  null-
     terminated
	byte string which is accessible through what().

	1) Default constructor.
	2) Copy constructor.
	If  *this and other both have dynamic type std::bad_alloc then std::str-
     cmp(what(),
	other.what()) == 0.
	(since C++11)

Parameters
	other - another exception object to copy

     std::bad_alloc::operator=

	bad_alloc& operator=( const bad_alloc& other ) throw();   (until C++11)
	bad_alloc& operator=( const bad_alloc& other ) noexcept;  (since C++11)

	Assigns the contents with those of other.
	If *this and other both have dynamic type std::bad_alloc then  std::str-
     cmp(what(),
	other.what()) == 0 after assignment.
	(since C++11)

Parameters
	other - another exception object to assign with

Return value
	*this

     std::bad_alloc::what

	virtual const char* what() const throw();   (until C++11)
	virtual const char* what() const noexcept;  (since C++11)

	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::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)

Example
     // Run this code

      #include <iostream>
      #include <new>

      int main()
      {
	  try
	  {
	      while (true)
	      {
		  new int[100000000ul];
	      }
	  }
	  catch (const std::bad_alloc& e)
	  {
	      std::cout << "Allocation failed: " << e.what() << '\n';
	  }
      }

Possible output:
      Allocation failed: std::bad_alloc

See also
	operator new   allocation functions
	operator new[] (function)

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