LWG3530 BUILTIN-PTR-MEOW should not opt the type out of syntactic checks

 - Ensure there is an \itemdecl for each operator().

Author: jensmaurer

source/utilities.tex

@@ -13978,21 +13978,10 @@
 
 \rSec3[comparisons.three.way]{Class \tcode{compare_three_way}}
 
-\pnum
-In this subclause, \tcode{\placeholdernc{BUILTIN-PTR-THREE-WAY}(T, U)}
-for types \tcode{T} and \tcode{U} is a boolean constant expression.
-\tcode{\placeholdernc{BUILTIN-PTR-THREE-WAY}(T, U)} is \tcode{true}
-if and only if \tcode{<=>} in the expression
-\begin{codeblock}
-declval<T>() <=> declval<U>()
-\end{codeblock}
-resolves to a built-in operator comparing pointers.
-
 \indexlibraryglobal{compare_three_way}%
 \begin{codeblock}
 struct compare_three_way {
   template<class T, class U>
-    requires @\libconcept{three_way_comparable_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-THREE-WAY}@(T, U)
     constexpr auto operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspec@;
@@ -14001,17 +13990,21 @@
 
 \begin{itemdecl}
 template<class T, class U>
-  requires @\libconcept{three_way_comparable_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-THREE-WAY}@(T, U)
   constexpr auto operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{three_way_comparable_with}.
+
 \pnum
 \expects
 If the expression \tcode{std::forward<T>(t) <=> std::forward<U>(u)} results in
 a call to a built-in operator \tcode{<=>} comparing pointers of type \tcode{P},
 the conversion sequences from both \tcode{T} and \tcode{U} to \tcode{P}
-are equality-preserving\iref{concepts.equality}.
+are equality-preserving\iref{concepts.equality};
+otherwise, \tcode{T} and \tcode{U} model \libconcept{three_way_comparable_with}.
 
 \pnum
 \effects
@@ -14033,32 +14026,33 @@
 
 \rSec2[range.cmp]{Concept-constrained comparisons}
 
-\pnum
-In this subclause, \tcode{\placeholdernc{BUILTIN-PTR-CMP}(T, $op$, U)} for types \tcode{T}
-and \tcode{U} and where $op$ is an equality\iref{expr.eq} or relational
-operator\iref{expr.rel} is a boolean constant expression.
-\tcode{\placeholdernc{BUILTIN-PTR-CMP}(T, $op$, U)} is \tcode{true} if and only if $op$
-in the expression \tcode{declval<T>() $op$ declval<U>()} resolves to a built-in
-operator comparing pointers.
-
 \indexlibraryglobal{equal_to}%
-\begin{itemdecl}
+\begin{codeblock}
 struct ranges::equal_to {
   template<class T, class U>
-    requires @\libconcept{equality_comparable_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(T, ==, U)
     constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
+\end{codeblock}
+
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{equality_comparable_with}.
+
 \pnum
 \expects
 If the expression \tcode{std::forward<T>(t) == std::forward<U>(u)}
 results in a call to a built-in operator \tcode{==} comparing pointers of type
 \tcode{P}, the conversion sequences from both \tcode{T} and \tcode{U} to \tcode{P}
-are equality-preserving\iref{concepts.equality}.
+are equality-preserving\iref{concepts.equality};
+otherwise, \tcode{T} and \tcode{U} model \libconcept{equality_comparable_with}.
 
 \pnum
 \effects
@@ -14077,61 +14071,89 @@
 \end{itemdescr}
 
 \indexlibraryglobal{not_equal_to}%
-\begin{itemdecl}
+\begin{codeblock}
 struct ranges::not_equal_to {
   template<class T, class U>
-    requires @\libconcept{equality_comparable_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(T, ==, U)
     constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
+\end{codeblock}
+
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
 \pnum
-\tcode{operator()} has effects equivalent to:
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{equality_comparable_with}.
+
+\pnum
+\effects
+Equivalent to:
 \begin{codeblock}
 return !ranges::equal_to{}(std::forward<T>(t), std::forward<U>(u));
 \end{codeblock}
 \end{itemdescr}
 
 \indexlibraryglobal{greater}%
-\begin{itemdecl}
+\begin{codeblock}
 struct ranges::greater {
   template<class T, class U>
-    requires @\libconcept{totally_ordered_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(U, <, T)
   constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
+\end{codeblock}
+
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
 \pnum
-\tcode{operator()} has effects equivalent to:
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{totally_ordered_with}.
+
+\pnum
+\effects
+Equivalent to:
 \begin{codeblock}
 return ranges::less{}(std::forward<U>(u), std::forward<T>(t));
 \end{codeblock}
 \end{itemdescr}
 
 \indexlibraryglobal{less}%
-\begin{itemdecl}
+\begin{codeblock}
 struct ranges::less {
   template<class T, class U>
-    requires @\libconcept{totally_ordered_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(T, <, U)
     constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
+\end{codeblock}
+
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
+\pnum
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{totally_ordered_with}.
+
 \pnum
 \expects
 If the expression \tcode{std::forward<T>(t) < std::forward<U>(u)} results in a
 call to a built-in operator \tcode{<} comparing pointers of type \tcode{P}, the
 conversion sequences from both \tcode{T} and \tcode{U} to \tcode{P} are
-equality-preserving\iref{concepts.equality}. For any expressions
+equality-preserving\iref{concepts.equality};
+otherwise, \tcode{T} and \tcode{U} model \libconcept{totally_ordered_with}.
+For any expressions
 \tcode{ET} and \tcode{EU} such that \tcode{decltype((ET))} is \tcode{T} and
 \tcode{decltype((EU))} is \tcode{U}, exactly one of
 \tcode{ranges::less\{\}(ET, EU)},
@@ -14156,19 +14178,28 @@
 \end{itemdescr}
 
 \indexlibraryglobal{greater_equal}%
-\begin{itemdecl}
+\begin{codeblock}
 struct ranges::greater_equal {
   template<class T, class U>
-    requires @\libconcept{totally_ordered_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(T, <, U)
     constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
+\end{codeblock}
+
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
 \end{itemdecl}
 
 \begin{itemdescr}
 \pnum
-\tcode{operator()} has effects equivalent to:
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{totally_ordered_with}.
+
+\pnum
+\effects
+Equivalent to:
 \begin{codeblock}
 return !ranges::less{}(std::forward<T>(t), std::forward<U>(u));
 \end{codeblock}
@@ -14178,16 +14209,25 @@
 \begin{itemdecl}
 struct ranges::less_equal {
   template<class T, class U>
-    requires @\libconcept{totally_ordered_with}@<T, U> || @\placeholdernc{BUILTIN-PTR-CMP}@(U, <, T)
     constexpr bool operator()(T&& t, U&& u) const;
 
   using is_transparent = @\unspecnc@;
 };
 \end{itemdecl}
 
+\begin{itemdecl}
+template<class T, class U>
+  constexpr bool operator()(T&& t, U&& u) const;
+\end{itemdecl}
+
 \begin{itemdescr}
 \pnum
-\tcode{operator()} has effects equivalent to:
+\constraints
+\tcode{T} and \tcode{U} satisfy \libconcept{totally_ordered_with}.
+
+\pnum
+\effects
+Equivalent to:
 \begin{codeblock}
 return !ranges::less{}(std::forward<U>(u), std::forward<T>(t));
 \end{codeblock}