CWG2237 Can a template-id name a constructor?

Author: Dawn Perchik

source/compatibility.tex

@@ -1863,6 +1863,26 @@
 if those entities are only referenced in contexts
 that do not result in an odr-use.
 
+\rSec2[diff.cpp17.special]{\ref{special}: special member functions}
+
+\diffrefs{class.ctor}{class.dtor}
+\change
+A \grammarterm{simple-template-id}
+is no longer valid as the \grammarterm{declarator-id} of a constructor or destructor.
+\rationale
+Remove potentially error-prone option for redundancy.
+\effect
+Valid \CppXVII{} code may fail to compile
+in this International Standard. For example:
+\begin{codeblock}
+template<class T>
+struct A {
+  A<T>();          // error: \grammarterm{simple-template-id} not allowed for constructor
+  A(int);          // OK, \grammarterm{injected-class-name} used
+  ~A<T>();         // error: \grammarterm{simple-template-id} not allowed for destructor
+};
+\end{codeblock}
+
 \rSec2[diff.cpp17.temp]{\ref{temp}: templates}
 
 \diffref{temp.names}

source/macros.tex

@@ -318,6 +318,7 @@
 %% Change descriptions
 \newcommand{\diffdef}[1]{\hfill\break\textbf{#1:}\space}
 \newcommand{\diffref}[1]{\pnum\textbf{Affected subclause:} \ref{#1}}
+\newcommand{\diffrefs}[2]{\pnum\textbf{Affected subclauses:} \ref{#1}, \ref{#2}}
 \newcommand{\change}{\diffdef{Change}}
 \newcommand{\rationale}{\diffdef{Rationale}}
 \newcommand{\effect}{\diffdef{Effect on original feature}}

source/special.tex

@@ -89,16 +89,10 @@
 \begin{itemize}
 \item
 in a \grammarterm{member-declaration} that belongs to the
-\grammarterm{member-specification} of a class but is not a friend
+\grammarterm{member-specification} of a class or class template
+but is not a friend
 declaration\iref{class.friend}, the \grammarterm{id-expression} is the
-injected-class-name\iref{class} of the immediately-enclosing class;
-
-\item
-in a \grammarterm{member-declaration} that belongs to the
-\grammarterm{member-specification} of a class template but is not a friend
-declaration, the \grammarterm{id-expression} is a \grammarterm{class-name} that
-names the current instantiation\iref{temp.dep.type} of the
-immediately-enclosing class template; or
+injected-class-name\iref{class} of the immediately-enclosing entity or
 
 \item
 in a declaration at namespace scope or in a friend declaration, the
@@ -1023,17 +1017,11 @@
 \begin{itemize}
 \item
 in a \grammarterm{member-declaration} that belongs to the
-\grammarterm{member-specification} of a class but is not a friend
+\grammarterm{member-specification} of a class or class template
+but is not a friend
 declaration\iref{class.friend}, the \grammarterm{id-expression} is
 \tcode{\~}\grammarterm{class-name} and the \grammarterm{class-name} is the
-injected-class-name\iref{class} of the immediately-enclosing class;
-
-\item
-in a \grammarterm{member-declaration} that belongs to the
-\grammarterm{member-specification} of a class template but is not a friend
-declaration, the \grammarterm{id-expression} is
-\tcode{\~}\grammarterm{class-name} and the \grammarterm{class-name} names the
-current instantiation\iref{temp.dep.type} of the immediately-enclosing class template; or
+injected-class-name\iref{class} of the immediately-enclosing entity or
 
 \item
 in a declaration at namespace scope or in a friend declaration, the