tmp/tmp9brikyck/{from.md → to.md}
RENAMED
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@@ -6,15 +6,15 @@ The library describes a standard set of requirements for *allocators*,
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which are class-type objects that encapsulate the information about an
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allocation model. This information includes the knowledge of pointer
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types, the type of their difference, the type of the size of objects in
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this allocation model, as well as the memory allocation and deallocation
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primitives for it. All of the string types [[strings]], containers
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[[containers]] (except `array`), string buffers and
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[[input.output]], and `match_results` [[re]] are
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of allocators.
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In
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- `T`, `U`, `C` denote any cv-unqualified object type
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[[term.object.type]],
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- `X` denotes an allocator class for type `T`,
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- `Y` denotes the corresponding allocator class for type `U`,
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@@ -110,11 +110,11 @@ typename X::difference_type
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between any two pointers in the allocation model.
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*Remarks:* Default: `pointer_traits<XX::pointer>::difference_type`
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``` cpp
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typename X::
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```
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*Result:* `Y`
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*Ensures:* For all `U` (including `T`), `YY::rebind_alloc<T>` is `X`.
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@@ -341,11 +341,11 @@ X u(std::move(b));
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*Ensures:* `u` is equal to the prior value of `X(b)`.
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*Throws:* Nothing.
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``` cpp
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a.construct(c, args)
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```
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*Result:* (not used)
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*Effects:* Constructs an object of type `C` at `c`.
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@@ -510,10 +510,29 @@ struct SimpleAllocator {
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};
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```
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— *end example*]
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##### Allocator completeness requirements <a id="allocator.requirements.completeness">[[allocator.requirements.completeness]]</a>
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If `X` is an allocator class for type `T`, `X` additionally meets the
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allocator completeness requirements if, whether or not `T` is a complete
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type:
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which are class-type objects that encapsulate the information about an
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allocation model. This information includes the knowledge of pointer
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types, the type of their difference, the type of the size of objects in
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this allocation model, as well as the memory allocation and deallocation
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primitives for it. All of the string types [[strings]], containers
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[[containers]] (except `array` and `inplace_vector`), string buffers and
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string streams [[input.output]], and `match_results` [[re]] are
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parameterized in terms of allocators.
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In [[allocator.requirements]],
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- `T`, `U`, `C` denote any cv-unqualified object type
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[[term.object.type]],
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- `X` denotes an allocator class for type `T`,
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- `Y` denotes the corresponding allocator class for type `U`,
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between any two pointers in the allocation model.
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*Remarks:* Default: `pointer_traits<XX::pointer>::difference_type`
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``` cpp
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typename X::rebind<U>::other
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```
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*Result:* `Y`
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*Ensures:* For all `U` (including `T`), `YY::rebind_alloc<T>` is `X`.
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*Ensures:* `u` is equal to the prior value of `X(b)`.
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*Throws:* Nothing.
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``` cpp
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a.construct(c, args...)
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```
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*Result:* (not used)
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*Effects:* Constructs an object of type `C` at `c`.
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};
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```
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— *end example*]
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The following exposition-only concept defines the minimal requirements
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on an Allocator type.
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``` cpp
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namespace std {
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template<class Alloc>
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concept simple-allocator =
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requires(Alloc alloc, size_t n) {
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{ *alloc.allocate(n) } -> same_as<typename Alloc::value_type&>;
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{ alloc.deallocate(alloc.allocate(n), n) };
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} &&
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copy_constructible<Alloc> &&
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equality_comparable<Alloc>;
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}
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```
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A type `Alloc` models `simple-allocator` if it meets the requirements of
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[[allocator.requirements.general]].
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##### Allocator completeness requirements <a id="allocator.requirements.completeness">[[allocator.requirements.completeness]]</a>
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If `X` is an allocator class for type `T`, `X` additionally meets the
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allocator completeness requirements if, whether or not `T` is a complete
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type:
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