LWG3657 std::hash<std::filesystem::path> is not enabled

Author: jensmaurer

source/iostreams.tex

@@ -12668,6 +12668,12 @@
   path weakly_canonical(const path& p, error_code& ec);
 }
 
+// \ref{fs.path.hash}, hash support
+namespace std {
+  template<class T> struct hash;
+  template<> struct hash<filesystem::path>;
+}
+
 namespace std::ranges {
   template<>
     inline constexpr bool enable_borrowed_range<filesystem::directory_iterator> = true;
@@ -14618,6 +14624,19 @@
 Equivalent to: \tcode{return path(lhs) /= rhs;}
 \end{itemdescr}
 
+\rSec3[fs.path.hash]{Hash support}
+
+\begin{itemdecl}
+template<> struct hash<filesystem::path>;
+\end{itemdecl}
+
+\begin{itemdescr}
+\pnum
+For an object \tcode{p} of type \tcode{filesystem::path},
+\tcode{hash<filesystem::path>()(p)} evaluates to the same result as
+\tcode{filesystem::hash_value(p)}.
+\end{itemdescr}
+
 \rSec2[fs.class.filesystem.error]{Class \tcode{filesystem_error}}
 
 \rSec3[fs.class.filesystem.error.general]{General}