Some cleanup in alspan.h

This commit is contained in:
Chris Robinson 2020-10-23 19:03:37 -07:00
parent 7cb1cc8ab5
commit 556321f18d

View File

@ -10,11 +10,11 @@
namespace al {
template<typename T>
constexpr auto size(T &cont) -> decltype(cont.size())
constexpr auto size(T &cont) noexcept(noexcept(cont.size())) -> decltype(cont.size())
{ return cont.size(); }
template<typename T>
constexpr auto size(const T &cont) -> decltype(cont.size())
constexpr auto size(const T &cont) noexcept(noexcept(cont.size())) -> decltype(cont.size())
{ return cont.size(); }
template<typename T, size_t N>
@ -27,11 +27,11 @@ constexpr size_t size(std::initializer_list<T> list) noexcept
template<typename T>
constexpr auto data(T &cont) -> decltype(cont.data())
constexpr auto data(T &cont) noexcept(noexcept(cont.data())) -> decltype(cont.data())
{ return cont.data(); }
template<typename T>
constexpr auto data(const T &cont) -> decltype(cont.data())
constexpr auto data(const T &cont) noexcept(noexcept(cont.data())) -> decltype(cont.data())
{ return cont.data(); }
template<typename T, size_t N>
@ -43,7 +43,9 @@ constexpr const T* data(std::initializer_list<T> list) noexcept
{ return list.begin(); }
template<typename T, size_t E=static_cast<size_t>(-1)>
constexpr size_t dynamic_extent{static_cast<size_t>(-1)};
template<typename T, size_t E=dynamic_extent>
class span;
namespace detail_ {
@ -82,8 +84,6 @@ namespace detail_ {
template<typename T, size_t E>
class span {
static constexpr size_t dynamic_extent{static_cast<size_t>(-1)};
public:
using element_type = T;
using value_type = std::remove_cv_t<T>;
@ -109,12 +109,15 @@ public:
constexpr span(element_type (&arr)[E]) noexcept : span{al::data(arr), al::size(arr)} { }
constexpr span(std::array<value_type,E> &arr) noexcept : span{al::data(arr), al::size(arr)} { }
template<REQUIRES(std::is_const<element_type>::value)>
constexpr span(const std::array<value_type,E> &arr) noexcept : span{al::data(arr), al::size(arr)} { }
constexpr span(const std::array<value_type,E> &arr) noexcept
: span{al::data(arr), al::size(arr)}
{ }
template<typename U, REQUIRES(IS_VALID_CONTAINER(U))>
constexpr span(U &cont) : span{al::data(cont), al::size(cont)} { }
template<typename U, REQUIRES(IS_VALID_CONTAINER(const U))>
constexpr span(const U &cont) : span{al::data(cont), al::size(cont)} { }
template<typename U, REQUIRES(!std::is_same<element_type,U>::value && std::is_convertible<U(*)[],element_type(*)[]>::value)>
template<typename U, REQUIRES(!std::is_same<element_type,U>::value
&& std::is_convertible<U(*)[],element_type(*)[]>::value)>
constexpr span(const span<U,E> &span_) noexcept : span{al::data(span_), al::size(span_)} { }
constexpr span(const span&) noexcept = default;
@ -136,8 +139,10 @@ public:
constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator{end()}; }
constexpr reverse_iterator rend() const noexcept { return reverse_iterator{begin()}; }
constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator{cend()}; }
constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator{cbegin()}; }
constexpr const_reverse_iterator crbegin() const noexcept
{ return const_reverse_iterator{cend()}; }
constexpr const_reverse_iterator crend() const noexcept
{ return const_reverse_iterator{cbegin()}; }
template<size_t C>
constexpr span<element_type,C> first() const
@ -167,16 +172,15 @@ public:
*/
constexpr span<element_type,dynamic_extent> first(size_t count) const;
constexpr span<element_type,dynamic_extent> last(size_t count) const;
constexpr span<element_type,dynamic_extent> subspan(size_t offset, size_t count=dynamic_extent) const;
constexpr span<element_type,dynamic_extent> subspan(size_t offset,
size_t count=dynamic_extent) const;
private:
pointer mData{nullptr};
};
template<typename T>
class span<T,static_cast<size_t>(-1)> {
static constexpr size_t dynamic_extent{static_cast<size_t>(-1)};
class span<T,dynamic_extent> {
public:
using element_type = T;
using value_type = std::remove_cv_t<T>;
@ -193,7 +197,7 @@ public:
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
static constexpr size_t extent{static_cast<size_t>(-1)};
static constexpr size_t extent{dynamic_extent};
constexpr span() noexcept = default;
constexpr span(pointer ptr, index_type count) : mData{ptr}, mDataEnd{ptr+count} { }
@ -203,12 +207,15 @@ public:
template<size_t N>
constexpr span(std::array<value_type,N> &arr) noexcept : span{al::data(arr), al::size(arr)} { }
template<size_t N, REQUIRES(std::is_const<element_type>::value)>
constexpr span(const std::array<value_type,N> &arr) noexcept : span{al::data(arr), al::size(arr)} { }
constexpr span(const std::array<value_type,N> &arr) noexcept
: span{al::data(arr), al::size(arr)}
{ }
template<typename U, REQUIRES(IS_VALID_CONTAINER(U))>
constexpr span(U &cont) : span{al::data(cont), al::size(cont)} { }
template<typename U, REQUIRES(IS_VALID_CONTAINER(const U))>
constexpr span(const U &cont) : span{al::data(cont), al::size(cont)} { }
template<typename U, size_t N, REQUIRES((!std::is_same<element_type,U>::value || extent != N) && std::is_convertible<U(*)[],element_type(*)[]>::value)>
template<typename U, size_t N, REQUIRES((!std::is_same<element_type,U>::value || extent != N)
&& std::is_convertible<U(*)[],element_type(*)[]>::value)>
constexpr span(const span<U,N> &span_) noexcept : span{al::data(span_), al::size(span_)} { }
constexpr span(const span&) noexcept = default;
@ -231,8 +238,10 @@ public:
constexpr reverse_iterator rbegin() const noexcept { return reverse_iterator{end()}; }
constexpr reverse_iterator rend() const noexcept { return reverse_iterator{begin()}; }
constexpr const_reverse_iterator crbegin() const noexcept { return const_reverse_iterator{cend()}; }
constexpr const_reverse_iterator crend() const noexcept { return const_reverse_iterator{cbegin()}; }
constexpr const_reverse_iterator crbegin() const noexcept
{ return const_reverse_iterator{cend()}; }
constexpr const_reverse_iterator crend() const noexcept
{ return const_reverse_iterator{cbegin()}; }
template<size_t C>
constexpr span<element_type,C> first() const
@ -279,7 +288,8 @@ constexpr inline auto span<T,E>::last(size_t count) const -> span<element_type,d
}
template<typename T, size_t E>
constexpr inline auto span<T,E>::subspan(size_t offset, size_t count) const -> span<element_type,dynamic_extent>
constexpr inline auto span<T,E>::subspan(size_t offset, size_t count) const
-> span<element_type,dynamic_extent>
{
return (offset > size()) ? span<element_type>{} :
(count >= size()-offset) ? span<element_type>{mData+offset, mData+extent} :