boostorg/core
1
0
Fork 1
mirror of https://github.com/boostorg/core.git synced 2025-11-29 13:50:10 +01:00
Code Issues Packages Projects Releases Wiki Activity

Update pointer_traits and to_address to reflect the design adopted for C++20

Browse Source
This commit is contained in:
Glen Fernandes
2018-01-27 04:35:35 -05:00
parent e5281335e0
commit 23f10ab4bf
5 changed files with 219 additions and 294 deletions
Download Patch File Download Diff File Expand all files Collapse all files

56
doc/pointer_traits.qbk
View File

@@ -1,5 +1,5 @@
[/
Copyright 2017 Glen Joseph Fernandes
Copyright 2017-2018 Glen Joseph Fernandes
(glenjofe@gmail.com)
Distributed under the Boost Software License, Version 1.0.
@@ -20,8 +20,10 @@ The header <boost/core/pointer_traits.hpp> provides the class template
`boost::pointer_traits` to facilitate use of pointer-like types. The C++11
standard library introduced `std::pointer_traits` along with an allocator
model which supported pointer-like types in addition to plain raw pointers.
This implementation also supports C++98, and adds additional functionality
for obtaining raw pointers from pointers.
This implementation also supports C++98.
It also provides the function template `boost::to_address` to obtain a raw
pointer from an object of any pointer-like type.
[endsect]
@@ -54,7 +56,6 @@ namespace boost {
template<class U> using rebind = typename rebind_to<U>::type;
static pointer pointer_to(``['see below]`` v);
static element_type* to_address(const pointer& v) noexcept;
};
template<class T> struct pointer_traits<T*> {
@@ -66,11 +67,13 @@ namespace boost {
template<class U> using rebind = typename rebind_to<U>::type;
static pointer pointer_to(``['see below]`` v) noexcept;
static element_type* to_address(pointer v) noexcept;
};
template<class T>
typename pointer_traits<T>::element_type* to_address(const T& v) noexcept;
constexpr T* to_address(T* v) noexcept;
template<class T>
auto to_address(const T& v) noexcept;
}
```
@@ -93,39 +96,44 @@ namespace boost {
[section Member functions]
[variablelist pointer_traits
[[`static pointer pointer_to(`['see below] `v);`]
[variablelist
[[`static pointer pointer_traits::pointer_to(`['see below] `v);`]
[[variablelist
[[Remark]
[If `element_type` is a void type, the type of `v` is unspecified; otherwise,
it is `element_type&`.]]
[[Returns]
[A pointer to `v` obtained by calling `T::pointer_to(v)`.]]]]]
[[`static element_type* to_address(const pointer& v) noexcept;`]
[[variablelist
[[Requires] [`v` is not a null pointer.]]
[[Returns]
[A pointer of type `element_type*` that references the same location
as the argument.]]]]]]
[variablelist pointer_traits<T*>
[[`static pointer pointer_to(`['see below] `v) noexcept;`]
[[`static pointer pointer_traits<T*>::pointer_to(`['see below] `v) noexcept;`]
[[variablelist
[[Remark]
[If `element_type` is a void type, the type of `v` is unspecified; otherwise,
it is `element_type&`.]]
[[Returns] [The result of `boost::addressof(v)`.]]]]]
[[Returns] [`addressof(v)`.]]]]]]
[endsect]
[section Optional members]
[variablelist
[[`static element_type* to_address(pointer v) noexcept;`]
[[variablelist [[Returns] [The value of `v`.]]]]]]
[[variablelist
[[Returns]
[A pointer of type `element_type*` that references the same location as the
argument `p`.]]
[[Note] [This function should be the inverse of `pointer_to`. If defined, it
customizes the behavior of the non-member function `to_address`.]]]]]]
[endsect]
[section Free functions]
[variablelist
[[`template<class T> typename pointer_traits<T>::element_type*
to_address(const T& v) noexcept;`]
[[variablelist [[Returns] [`boost::pointer_traits<T>::to_address(v)`.]]]]]]
[[`template<class T> constexpr T* to_address(T* v) noexcept;`]
[[variablelist [[Returns] [`v`.]]]]]
[[`template<class T> auto to_address(const T& v) noexcept;`]
[[variablelist [[Returns] [`pointer_traits<T>::to_address(v)` if that
expression is well-formed, otherwise `to_address(v.operator->())`.]]]]]]
[endsect]
@@ -133,8 +141,8 @@ namespace boost {
[section Acknowledgments]
Glen Fernandes implemented `pointer_traits` with reviews and guidance from
Peter Dimov.
Glen Fernandes implemented `pointer_traits` and `to_address` with reviews and
guidance from Peter Dimov.
[endsect]