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[ranges] Introduce bidirectional-common and random-access-sized to simplify concept spelling #6654

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[ranges] Introduce bidirectional-common and random-access-sized to simplify concept spelling #6654

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302e4b5
[ranges] Introduce bidirectional-common and random-access-sized conce…
hewillk Nov 11, 2023
8e44dc8
fix wide line
hewillk Nov 11, 2023
9180dfb
Update source/ranges.tex
hewillk Nov 11, 2023
eb28501
Revert zip-is-common changes
hewillk Nov 11, 2023
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81 changes: 37 additions & 44 deletions source/ranges.tex
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Original file line number Diff line number Diff line change
Expand Up @@ -1642,6 +1642,14 @@
concept @\defexposconceptnc{range-with-movable-references}@ = // \expos
@\libconcept{input_range}@<R> && @\libconcept{move_constructible}@<range_reference_t<R>> &&
@\libconcept{move_constructible}@<range_rvalue_reference_t<R>>;

template<class R>
concept @\defexposconcept{bidirectional-common}@ = // \expos
@\libconcept{bidirectional_range}@<R> && @\libconcept{common_range}@<R>;

template<class R>
concept @\defexposconcept{random-access-sized}@ = // \expos
@\libconcept{random_access_range}@<R> && @\libconcept{sized_range}@<R>;
\end{codeblock}

\rSec2[view.interface]{View interface}
Expand Down Expand Up @@ -1723,9 +1731,8 @@
constexpr decltype(auto) front() requires @\libconcept{forward_range}@<D>;
constexpr decltype(auto) front() const requires @\libconcept{forward_range}@<const D>;

constexpr decltype(auto) back() requires @\libconcept{bidirectional_range}@<D> && @\libconcept{common_range}@<D>;
constexpr decltype(auto) back() const
requires @\libconcept{bidirectional_range}@<const D> && @\libconcept{common_range}@<const D>;
constexpr decltype(auto) back() requires @\exposconcept{bidirectional-common}@<D>;
constexpr decltype(auto) back() const requires @\exposconcept{bidirectional-common}@<const D>;

template<@\libconcept{random_access_range}@ R = D>
constexpr decltype(auto) operator[](range_difference_t<R> n) {
Expand Down Expand Up @@ -1766,9 +1773,8 @@

\indexlibrarymember{back}{view_interface}%
\begin{itemdecl}
constexpr decltype(auto) back() requires @\libconcept{bidirectional_range}@<D> && @\libconcept{common_range}@<D>;
constexpr decltype(auto) back() const
requires @\libconcept{bidirectional_range}@<const D> && @\libconcept{common_range}@<const D>;
constexpr decltype(auto) back() requires @\exposconcept{bidirectional-common}@<D>;
constexpr decltype(auto) back() const requires @\exposconcept{bidirectional-common}@<const D>;;
\end{itemdecl}

\begin{itemdescr}
Expand Down Expand Up @@ -5677,14 +5683,14 @@

\item
Otherwise, if \tcode{T} models
\libconcept{random_access_range} and \libconcept{sized_range}
\exposconcept{random-access-sized}
and is a specialization of
\tcode{span}\iref{views.span},
\tcode{basic_string_view}\iref{string.view}, or
\tcode{subrange}\iref{range.subrange},
then
\tcode{U(ranges::begin(E),
ranges::be\-gin(E) + std::min<D>(ranges::distance(E), F))},
ranges::be\-gin(E) + std::\linebreak{}min<D>(ranges::distance(E), F))},
except that \tcode{E} is evaluated only once,
where \tcode{U} is a type determined as follows:

Expand All @@ -5700,10 +5706,10 @@
\item
otherwise, if \tcode{T} is
a specialization of \tcode{iota_view}\iref{range.iota.view}
that models \libconcept{random_access_range} and \libconcept{sized_range},
that models \exposconcept{random-access-sized},
then
\tcode{iota_view(*ranges::begin(E),
*(ranges::begin(E) + std::\linebreak{}min<D>(ranges::distance(E), F)))},
*(ranges::begin(E) + std::min<D>(ranges::distance(E), \linebreak{}F)))},
except that \tcode{E} is evaluated only once.

\item
Expand Down Expand Up @@ -6142,7 +6148,7 @@

\item
Otherwise, if \tcode{T} models
\libconcept{random_access_range} and \libconcept{sized_range}
\exposconcept{random-access-sized}
and is
\begin{itemize}
\item a specialization of \tcode{span}\iref{views.span},
Expand All @@ -6160,12 +6166,12 @@
Otherwise,
if \tcode{T} is
a specialization of \tcode{subrange}\iref{range.subrange}
that models \libconcept{random_access_range} and \libconcept{sized_range},
that models \exposconcept{random-access-sized},
then
\tcode{T(ranges::begin(E) + std::min<D>(ranges::distance(E), F), ranges::\linebreak{}end(E),
\tcode{T(ranges::begin(E) + std::min<D>(ranges::distance(E), F), ranges::end(E),\linebreak{}
\exposid{to-unsigned-like}(ranges::distance(E) -
std::min<D>(ranges::distance(E), F)))},
except that \tcode{E} and \tcode{F} are each evaluated only once.
except\linebreak{} that \tcode{E} and \tcode{F} are each evaluated only once.

\item
Otherwise, if \tcode{T} is
Expand Down Expand Up @@ -6215,10 +6221,8 @@
constexpr V base() && { return std::move(@\exposid{base_}@); }

constexpr auto begin()
requires (!(@\exposconcept{simple-view}@<V> &&
@\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>));
constexpr auto begin() const
requires @\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>;
requires (!(@\exposconcept{simple-view}@<V> && @\exposconcept{random-access-sized}@<const V>));
constexpr auto begin() const requires @\exposconcept{random-access-sized}@<const V>;

constexpr auto end() requires (!@\exposconcept{simple-view}@<V>)
{ return ranges::end(@\exposid{base_}@); }
Expand Down Expand Up @@ -6267,10 +6271,8 @@
\indexlibrarymember{begin}{drop_view}%
\begin{itemdecl}
constexpr auto begin()
requires (!(@\exposconcept{simple-view}@<V> &&
@\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>));
constexpr auto begin() const
requires @\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>;
requires (!(@\exposconcept{simple-view}@<V> && @\exposconcept{random-access-sized}@<const V>));
constexpr auto begin() const requires @\exposconcept{random-access-sized}@<const V>;
\end{itemdecl}

\begin{itemdescr}
Expand Down Expand Up @@ -6578,13 +6580,11 @@

constexpr @\exposid{iterator}@& operator--()
requires @\exposid{ref-is-glvalue}@ && @\libconcept{bidirectional_range}@<@\exposid{Base}@> &&
@\libconcept{bidirectional_range}@<range_reference_t<@\exposid{Base}@>> &&
@\libconcept{common_range}@<range_reference_t<@\exposid{Base}@>>;
@\exposconcept{bidirectional-common}@<range_reference_t<@\exposid{Base}@>>;

constexpr @\exposid{iterator}@ operator--(int)
requires @\exposid{ref-is-glvalue}@ && @\libconcept{bidirectional_range}@<@\exposid{Base}@> &&
@\libconcept{bidirectional_range}@<range_reference_t<@\exposid{Base}@>> &&
@\libconcept{common_range}@<range_reference_t<@\exposid{Base}@>>;
@\exposconcept{bidirectional-common}@<range_reference_t<@\exposid{Base}@>>;

friend constexpr bool operator==(const @\exposid{iterator}@& x, const @\exposid{iterator}@& y)
requires @\exposid{ref-is-glvalue}@ && @\libconcept{forward_range}@<@\exposid{Base}@> &&
Expand All @@ -6607,8 +6607,7 @@
\begin{itemize}
\item If \exposid{ref-is-glvalue} is \tcode{true},
\exposid{Base} models \libconcept{bidirectional_range}, and
\tcode{range_reference_t<\exposid{Base}>} models
both \libconcept{bidirectional_range} and \libconcept{common_range},
\tcode{range_reference_t<\exposid{Base}>} models \exposconcept{bidirectional-common},
then \tcode{iterator_concept} denotes \tcode{bidirectio\-nal_iterator_tag}.
\item Otherwise, if \exposid{ref-is-glvalue} is \tcode{true} and
\exposid{Base} and \tcode{range_reference_t<\exposid{Base}>}
Expand Down Expand Up @@ -6811,8 +6810,7 @@
\begin{itemdecl}
constexpr @\exposid{iterator}@& operator--()
requires @\exposid{ref-is-glvalue}@ && @\libconcept{bidirectional_range}@<@\exposid{Base}@> &&
@\libconcept{bidirectional_range}@<range_reference_t<@\exposid{Base}@>> &&
@\libconcept{common_range}@<range_reference_t<@\exposid{Base}@>>;
@\exposconcept{bidirectional-common}@<range_reference_t<@\exposid{Base}@>>;
\end{itemdecl}

\begin{itemdescr}
Expand All @@ -6833,8 +6831,7 @@
\begin{itemdecl}
constexpr @\exposid{iterator}@ operator--(int)
requires @\exposid{ref-is-glvalue}@ && @\libconcept{bidirectional_range}@<@\exposid{Base}@> &&
@\libconcept{bidirectional_range}@<range_reference_t<@\exposid{Base}@>> &&
@\libconcept{common_range}@<range_reference_t<@\exposid{Base}@>>;
@\exposconcept{bidirectional-common}@<range_reference_t<@\exposid{Base}@>>;
\end{itemdecl}

\begin{itemdescr}
Expand Down Expand Up @@ -6979,9 +6976,6 @@
@\libconcept{common_reference_with}@<range_reference_t<R>, range_reference_t<P>> &&
@\libconcept{common_reference_with}@<range_rvalue_reference_t<R>, range_rvalue_reference_t<P>>;

template<class R>
concept @\defexposconcept{bidirectional-common}@ = @\libconcept{bidirectional_range}@<R> && @\libconcept{common_range}@<R>; // \expos

template<@\libconcept{input_range}@ V, @\libconcept{forward_range}@ Pattern>
requires @\libconcept{view}@<V> && @\libconcept{input_range}@<range_reference_t<V>>
&& @\libconcept{view}@<Pattern>
Expand Down Expand Up @@ -8531,28 +8525,28 @@
constexpr V base() && { return std::move(@\exposid{base_}@); }

constexpr auto begin() {
if constexpr (@\libconcept{random_access_range}@<V> && @\libconcept{sized_range}@<V>)
if constexpr (@\exposconcept{random-access-sized}@<V>)
return ranges::begin(@\exposid{base_}@);
else
return common_iterator<iterator_t<V>, sentinel_t<V>>(ranges::begin(@\exposid{base_}@));
}

constexpr auto begin() const requires @\libconcept{range}@<const V> {
if constexpr (@\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>)
if constexpr (@\exposconcept{random-access-sized}@<const V>)
return ranges::begin(@\exposid{base_}@);
else
return common_iterator<iterator_t<const V>, sentinel_t<const V>>(ranges::begin(@\exposid{base_}@));
}

constexpr auto end() {
if constexpr (@\libconcept{random_access_range}@<V> && @\libconcept{sized_range}@<V>)
if constexpr (@\exposconcept{random-access-sized}@<V>)
return ranges::begin(@\exposid{base_}@) + ranges::distance(@\exposid{base_}@);
else
return common_iterator<iterator_t<V>, sentinel_t<V>>(ranges::end(@\exposid{base_}@));
}

constexpr auto end() const requires @\libconcept{range}@<const V> {
if constexpr (@\libconcept{random_access_range}@<const V> && @\libconcept{sized_range}@<const V>)
if constexpr (@\exposconcept{random-access-sized}@<const V>)
return ranges::begin(@\exposid{base_}@) + ranges::distance(@\exposid{base_}@);
else
return common_iterator<iterator_t<const V>, sentinel_t<const V>>(ranges::end(@\exposid{base_}@));
Expand Down Expand Up @@ -13359,11 +13353,11 @@
\begin{codeblock}
namespace std::ranges {
template<class V>
concept @\defexposconcept{slide-caches-nothing}@ = @\libconcept{random_access_range}@<V> && @\libconcept{sized_range}@<V>; // \expos
concept @\defexposconcept{slide-caches-nothing}@ = @\exposconcept{random-access-sized}@<V>; // \expos

template<class V>
concept @\defexposconcept{slide-caches-last}@ = // \expos
!@\exposconcept{slide-caches-nothing}@<V> && @\libconcept{bidirectional_range}@<V> && @\libconcept{common_range}@<V>;
!@\exposconcept{slide-caches-nothing}@<V> && @\exposconcept{bidirectional-common}@<V>;

template<class V>
concept @\defexposconcept{slide-caches-first}@ = // \expos
Expand Down Expand Up @@ -14969,12 +14963,11 @@
template<bool Const, class First, class... Vs>
concept @\defexposconcept{cartesian-product-is-random-access}@ = // \expos
(@\libconcept{random_access_range}@<@\exposid{maybe-const}@<Const, First>> && ... &&
(@\libconcept{random_access_range}@<@\exposid{maybe-const}@<Const, Vs>>
&& @\libconcept{sized_range}@<@\exposid{maybe-const}@<Const, Vs>>));
@\exposconcept{random-access-sized}@<@\exposid{maybe-const}@<Const, Vs>>);

template<class R>
concept @\defexposconcept{cartesian-product-common-arg}@ = // \expos
@\libconcept{common_range}@<R> || (@\libconcept{sized_range}@<R> && @\libconcept{random_access_range}@<R>);
@\libconcept{common_range}@<R> || @\exposconcept{random-access-sized}@<R>;

template<bool Const, class First, class... Vs>
concept @\defexposconcept{cartesian-product-is-bidirectional}@ = // \expos
Expand Down