intro/enum_simple: improve parsing for multi-level namespaces

introspection/enum_simple.hpp

@@ -19,7 +19,7 @@ namespace cruft::introspection {
         ///
         /// It must include an enum literal.
         template <typename EnumT, EnumT Value>
-        static constexpr
+        static consteval
         std::string_view
         enum_pretty_function (void)
         {
@@ -39,20 +39,22 @@ namespace cruft::introspection {
     /// namespace. Testing is _essential_.
     template <typename EnumT, EnumT Value>
     requires (std::is_enum_v<EnumT>)
-    constexpr std::string_view
+    consteval std::string_view
     to_string [[maybe_unused]] (void)
     {
 #if defined(__clang__)
         // std::string_view cruft::introspection::detail::enum_pretty_function() [EnumT = enum_t, Value = main()::value0]
         //
         // std::string_view enum_pretty_function() [EnumT = enum_t, Value = (enum_t)42]
+        //
+        // "std::string_view cruft::introspection::detail::enum_pretty_function() [EnumT = enum_t, Value = test_local(cruft::TAP::logger &)::value0]"
 
         auto const signature = detail::enum_pretty_function<EnumT, Value> ();
 
         auto const comma  = signature.find (',');
-        auto const coloncolon = signature.find ("::", comma + 1);
-        auto const equals = signature.find ('=', comma + 1);
         auto const close  = signature.find (']', comma + 1);
+        auto const coloncolon = signature.rfind ("::", close);
+        auto const equals = signature.find ('=', comma + 1);
 
         auto const first = coloncolon == std::string_view::npos ? equals + 2 : coloncolon + 2;
 
@@ -64,11 +66,13 @@ namespace cruft::introspection {
         // "constexpr std::string_view cruft::introspection::detail::enum_pretty_function() [with EnumT = main()::enum_t; EnumT Value = main::value1; std::string_view = std::basic_string_view<char>]"
         //
         // consteval std::string_view enum_pretty_function() [with EnumT = enum_t; EnumT Value = (enum_t)42; std::string_view = std::basic_string_view<char>]
+        //
+        // "constexpr std::string_view cruft::introspection::detail::enum_pretty_function() [with EnumT = test_local(cruft::TAP::logger&)::enum_t; EnumT Value = test_local::value0; std::string_view = std::basic_string_view<char>]"
 
         auto const signature = detail::enum_pretty_function<EnumT, Value> ();
         auto const semicolon0 = signature.find (';');
         auto const semicolon1 = signature.find (';',  semicolon0 + 1);
-        auto const coloncolon = signature.find ("::", semicolon0 + 1);
+        auto const coloncolon = signature.rfind ("::", semicolon1);
         auto const equals     = signature.find ('=',  semicolon0);
 
         // static_assert (equals > semicolon0);
@@ -121,11 +125,11 @@ namespace cruft::introspection {
             // If the bounds here are incorrect then the result will never be found.
             // It should be possible to change this search range fairly easily, though
             // for larger values you might run into compile time recursion limits.
-            static
+            static constexpr
             EnumT
             from (std::string_view name)
             {
-                return _from<EnumT (0), EnumT (128)> (name);
+                return _from<EnumT (0), EnumT (5)> (name);
             }
 
 
@@ -147,7 +151,8 @@ namespace cruft::introspection {
                 }
             }
 
-            static std::string_view
+            static constexpr
+            std::string_view
             to (EnumT val)
             {
                 return _to<EnumT (0), EnumT (128)> (val);
@@ -158,6 +163,7 @@ namespace cruft::introspection {
 
     template <typename EnumT>
     requires (std::is_enum_v<EnumT>)
+    constexpr
     EnumT
     from_string (std::string_view str)
     {
@@ -167,6 +173,7 @@ namespace cruft::introspection {
 
     template <typename EnumT>
     requires (std::is_enum_v<EnumT>)
+    constexpr
     std::string_view
     to_string (EnumT val)
     {

test/introspection/enum_simple.cpp

@@ -4,18 +4,63 @@
 #include <iostream>
 
 
+///////////////////////////////////////////////////////////////////////////////
+namespace foo::bar {
+    enum qux_t {
+        qux0,
+        qux1,
+    };
+}
+
+
+//-----------------------------------------------------------------------------
+static void
+test_local (cruft::TAP::logger &tap)
+{
+    enum enum_t { value0 = 0, value1 = 1, value3 = 3, };
+
+    tap.expect_eq (cruft::introspection::from_string<enum_t> ("value1"), value1, "from_string, dynamic");
+    tap.expect_eq (cruft::introspection::to_string<enum_t, value1> (), "value1", "to_string, static");
+    tap.expect_eq (cruft::introspection::to_string (value1), "value1", "to_string, dynamic");
+}
+
+
+//-----------------------------------------------------------------------------
+static void
+test_namespaced (cruft::TAP::logger &tap)
+{
+    auto const val = cruft::introspection::to_string<foo::bar::qux_t, foo::bar::qux1> ();
+    (void)val;
+
+    tap.expect_eq (
+        cruft::introspection::from_string<foo::bar::qux_t> ("qux1"),
+        foo::bar::qux1,
+        "namespaced: from_string, dynamic"
+    );
+    tap.expect_eq (
+        cruft::introspection::to_string<
+            foo::bar::qux_t,
+            foo::bar::qux1
+        > (),
+        "qux1",
+        "namespaced: to_string, static"
+    );
+    tap.expect_eq (
+        cruft::introspection::to_string(foo::bar::qux1),
+        "qux1",
+        "namespaced: to-string, dynamic"
+    );
+}
+
+
+//-----------------------------------------------------------------------------
 int
 main ()
 {
     cruft::TAP::logger tap;
 
-    enum enum_t { value0 = 0, value1 = 1, value3 = 3, };
+    test_local (tap);
-
+    test_namespaced (tap);
-    std::cout << cruft::introspection::detail::enum_pretty_function<enum_t, value0> () << '\n';
-
-    tap.expect_eq (cruft::introspection::from_string<enum_t> ("value1"), value1, "from_string, dynamic");
-    tap.expect_eq (cruft::introspection::to_string<enum_t, value1> (), "value1", "to_string, static");
-    tap.expect_eq (cruft::introspection::to_string (value1), "value1", "to_string, dynamic");
 
     return tap.status ();
 }