[range.range] [span.cons] Update remaining uses of removed

exposition-only concepts range-impl and forwarding-range with range and
safe_range as appropriate.

Author: zygoloid

papers/nxxxx.md

@@ -63,6 +63,20 @@ and after consulting the paper authors and the LWG chair,
 the corresponding changes were also applied to
 the additional range adaptors listed above.
 
+### LWG motion 16
+
+This paper removed the exposition-only concept *`range-impl`*,
+inlining it into its only remaining user, the `range` concept.
+However, two uses of *`range-impl`* were left behind.
+These have been updated and suitably adjusted
+to refer to `range` instead.
+
+LWG motion 13 ([P1394R4](http://wg21.link/p1394r4))
+added a couple of new uses of
+the exposition-only concept *`forwarding-range`*,
+which was removed by this paper.
+These uses have been replaced with `safe_range`.
+
 ## Feature test macros
 
 The feature test macro `__cpp_nontype_template_parameter_class` has been removed

source/containers.tex

@@ -10786,7 +10786,7 @@
 \item \tcode{extent == dynamic_extent} is \tcode{true}.
 \item \tcode{R} satisfies \tcode{ranges::\libconcept{contiguous_range}} and
   \tcode{ranges::\libconcept{sized_range}}.
-\item Either \tcode{R} satisfies \exposconcept{forwarding-range} or
+\item Either \tcode{R} satisfies \libconcept{safe_range} or
 \tcode{is_const_v<element_type>} is \tcode{true}.
 \item \tcode{remove_cvref_t<R>} is not a specialization of \tcode{span}.
 \item \tcode{remove_cvref_t<R>} is not a specialization of \tcode{array}.
@@ -10805,7 +10805,7 @@
 \item \tcode{R} models \tcode{ranges::\libconcept{contiguous_range}} and
 \tcode{ranges::\libconcept{sized_range}}.
 \item If \tcode{is_const_v<element_type>} is \tcode{false},
-\tcode{R} models \exposconcept{forwarding-range}.
+\tcode{R} models \libconcept{safe_range}.
 \end{itemize}
 
 \pnum

source/ranges.tex

@@ -796,27 +796,27 @@
 \begin{itemdescr}
 \pnum
 The required expressions
-\tcode{ranges::begin(std::forward<T>(t))}
+\tcode{ranges::begin(t)}
 and
-\tcode{ranges::end(std::forward<\brk{}T>(t))}
-of the \exposconcept{range-impl} concept
+\tcode{ranges::end(t)}
+of the \libconcept{range} concept
 do not require implicit expression variations\iref{concepts.equality}.
 
 \pnum
-Given an expression \tcode{E} such that \tcode{decltype((E))} is \tcode{T},
-\tcode{T} models \tcode{\placeholder{range-impl}} only if
+Given an expression \tcode{t} such that \tcode{decltype((t))} is \tcode{T\&},
+\tcode{T} models \libconcept{range} only if
 \begin{itemize}
-\item \range{ranges::begin(E)}{ranges::end(E)}
+\item \range{ranges::begin(t)}{ranges::end(t)}
   denotes a range\iref{iterator.requirements.general},
 
 \item both
-\tcode{ranges::begin(E)}
+\tcode{ranges::begin(t)}
 and
-\tcode{ranges::end(E)}
+\tcode{ranges::end(t)}
 are amortized constant time and non-modifying, and
 
-\item if the type of \tcode{ranges::begin(E)} models
-\libconcept{forward_iterator}, \tcode{ranges::begin(E)} is equality-preserving.
+\item if the type of \tcode{ranges::begin(t)} models
+\libconcept{forward_iterator}, \tcode{ranges::begin(t)} is equality-preserving.
 \end{itemize}
 
 \pnum