bit::memory::null_allocator Class Reference

An allocator that only ever serves nullptr. More...

#include <null_allocator.hpp>

Public Types
using	default_alignment = std::integral_constant< std::size_t, 1 >

Public Member Functions
	null_allocator ()=default
	Default-constructs a null_allocator.
	null_allocator (null_allocator &&other) noexcept=default
	Move-constructs a null_allocator from another allocator. More...
	null_allocator (const null_allocator &other) noexcept=default
	Copy-constructs a null_allocator from another allocator. More...
null_allocator &	operator= (null_allocator &&other) noexcept=default
	Move-assigns a null_allocator from another allocator. More...
null_allocator &	operator= (const null_allocator &other) noexcept=default
	Copy-assigns a null_allocator from another allocator. More...
owner< void * >	try_allocate (std::size_t size, std::size_t align, std::size_t offset=0) noexcept
	Allocates a null pointer. More...
void	deallocate (owner< void *> p, std::size_t n) noexcept
	Deallocates a pointer previously allocated with a call to allocate. More...
bool	owns (const void *p) const noexcept
	Checks if the pointer p is contained in the null_allocator. More...
bool	owns (std::nullptr_t) const noexcept
	Checks if nullptr is part of this allocator. More...
allocator_info	info () const noexcept
	Gets the info about this allocator. More...

Detailed Description

An allocator that only ever serves nullptr.

As is expected, the size and alignment of the allocation will always be ignored, since this only returns nullptr.

Invoking null_allocator::deallocate on a pointer has no effect, but is considered bad-practice, since this allocator could never produce a valid allocation.

Satisfies

ExtendedAllocator

Satisfies

Stateless

Definition at line 61 of file null_allocator.hpp.

Constructor & Destructor Documentation

null_allocator() [1/2]

bit::memory::null_allocator::null_allocator ( null_allocator &&  other )

defaultnoexcept

Move-constructs a null_allocator from another allocator.

Parameters

other

the other null_allocator to move

null_allocator() [2/2]

bit::memory::null_allocator::null_allocator ( const null_allocator &  other )

defaultnoexcept

Copy-constructs a null_allocator from another allocator.

Parameters

other

the other null_allocator to copy

Member Function Documentation

deallocate()

void bit::memory::null_allocator::deallocate ( owner< void *>  p, std::size_t  n  )

noexcept

Deallocates a pointer previously allocated with a call to allocate.

Parameters

p	the pointer to deallocate
n	the number of entries previously allocated

info()

allocator_info bit::memory::null_allocator::info ( ) const

noexcept

Gets the info about this allocator.

This defaults to 'null_allocator'. Use a named_null_allocator to override this

Returns

the info for this allocator

operator=() [1/2]

null_allocator& bit::memory::null_allocator::operator= ( null_allocator &&  other )

defaultnoexcept

Move-assigns a null_allocator from another allocator.

Parameters

other

the other null_allocator to move

Returns

reference to (*this)

operator=() [2/2]

null_allocator& bit::memory::null_allocator::operator= ( const null_allocator &  other )

defaultnoexcept

Copy-assigns a null_allocator from another allocator.

Parameters

other

the other null_allocator to copy

Returns

reference to (*this)

owns() [1/2]

bool bit::memory::null_allocator::owns ( const void *  p ) const

noexcept

Checks if the pointer p is contained in the null_allocator.

Parameters

p	the pointer to check

Returns

true if p is nullptr

owns() [2/2]

bool bit::memory::null_allocator::owns ( std::nullptr_t  ) const

noexcept

Checks if nullptr is part of this allocator.

Returns

true

try_allocate()

owner<void*> bit::memory::null_allocator::try_allocate ( std::size_t  size, std::size_t  align, std::size_t  offset = 0  )

noexcept

Allocates a null pointer.

Parameters

size	the size of the allocation
align	the alignment of the allocation

Returns

nullptr

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The documentation for this class was generated from the following file:

• null_allocator.hpp