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std::alloca...ts::allocate(3)  C++ Standard Libary std::alloca...ts::allocate(3)

NAME
     std::allocator_traits::allocate - std::allocator_traits::allocate

Synopsis
	Defined in header <memory>
	static pointer allocate( Alloc& a, size_type n		 (since C++11)
	);							 (until C++20)
	[[nodiscard]] static constexpr pointer allocate(	 (since C++20)
	Alloc& a, size_type n );
	static	    pointer	allocate(     Alloc&	 a,	size_type     n,
     (since C++11)
				 const_void_pointer	      hint	     (1)
     (until C++20)
	);
	[[nodiscard]] static constexpr pointer allocate(     (2)
	Alloc&			a,		    size_type		      n,
     (since C++20)

	 const_void_pointer hint );

	Uses the allocator a to allocate n * sizeof(Alloc::value_type) bytes of
	uninitialized storage. An array of type Alloc::value_type[n] is  created
     in the
	storage, but none of its elements are constructed.

	1) Calls a.allocate(n).
	2)  Additionally  passes  memory locality hint hint. Calls a.allocate(n,
     hint) if
	possible. If not possible (e.g. a has no  two-argument	member	function
     allocate),
	calls a.allocate(n).

Parameters
	a    - allocator to use
	n    - the number of objects to allocate storage for
	hint - pointer to a nearby memory location

Return value
	The pointer returned by the call to a.allocate(n).

Notes
	Alloc::allocate  was  not required to create array object until P0593R6,
     which made
	using non-default allocator for std::vector and  some  other  containers
     not
	well-defined according to a strict reading of the core language specifi-
     cation.

	After  calling	allocate  and  before  construction of elements, pointer
     arithmetic of
	Alloc::value_type* is well-defined within the allocated array,	but  the
     behavior is
	undefined if elements are accessed.

Example
	 This section is incomplete
	 Reason: no example

See also
	allocate allocates uninitialized storage
		 (public member function of std::allocator<T>)

Category:
	  * Todo no example

http://cppreference.com 	   2024.06.10	   std::alloca...ts::allocate(3)
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