Some cleanup and tests for Enum and constexpr strings.

CMakeLists.txt

@@ -31,6 +31,7 @@ add_subdirectory( Utility )
 
 # The local subdir tests to build
 add_subdirectory( AutoRAII.test )
+add_subdirectory( Enum.test )
 add_subdirectory( comparisons.test )
 add_subdirectory( Exception.test )
 add_subdirectory( word_wrap.test )

ConstexprString.h

@@ -24,6 +24,11 @@ namespace Alepha::Hydrogen  ::detail::  ConstexprString_m
 		// benefit of the NTTP variadic list way, for compiler memory usage, is that
 		// the a type using the string as a parameter has a symbol size which
 		// is proportional to the number of chars in the string.
+		//
+		// However, NTTP parameters are pretty large in terms of memory footprint
+		// of the compiler and they do tax the compiler's CPU usage a lot more.
+		// As such, compile time strings of a "reasonable" size are probably the
+		// best we can hope for.
 		const std::size_t maxSize= 128;
 	}
 
@@ -47,7 +52,7 @@ namespace Alepha::Hydrogen  ::detail::  ConstexprString_m
 					const char *
 					what() const noexcept final
 					{
-						return "Failure  to allocate enough space for a a compile-time string.";
+						return "Failure to allocate enough space for a a compile-time string.";
 					}
 			};
 

Enum.h

@@ -19,7 +19,7 @@ static_assert( __cplusplus > 2020'99 );
 #include "ConstexprString.h"
 #include "meta.h"
 
-namespace Alepha::Hydrogen  ::detail:: Enum_m
+namespace Alepha::Hydrogen  ::detail::  Enum_m
 {
 	inline namespace exports {}
 
@@ -52,13 +52,6 @@ namespace Alepha::Hydrogen  ::detail:: Enum_m
 		}
 	}
 
-	template< auto value, auto ... >
-	constexpr decltype( auto )
-	get_first_enum_string()
-	{
-		return value;
-	}
-
 	template< ConstexprString s >
 	struct EnumValueString
 	{
@@ -121,8 +114,6 @@ namespace Alepha::Hydrogen  ::detail:: Enum_m
 
 	template< EnumValueString ... values >
 	class exports::Enum
-		//: private comparable
-		// Alepha::Hydrogen comparables work differently than the one-off Cavorite form.
 	{
 		private:
 			enum class StrictInteger : unsigned {};
@@ -197,8 +188,6 @@ namespace Alepha::Hydrogen  ::detail:: Enum_m
 
 			constexpr unsigned get_index() const { return static_cast< unsigned >( value ); }
 
-			constexpr auto equality_lens() const { return value; }
-
 			bool operator == ( const Enum & ) const= default;
 
 			friend std::ostream &

Enum.test/0.cc

@@ -0,0 +1,61 @@
+static_assert( __cplusplus > 2020'99 );
+
+#include "../Enum.h"
+
+#include <Alepha/Testing/test.h>
+#include <Alepha/Testing/TableTest.h>
+
+#include <Alepha/Utility/evaluation_helpers.h>
+
+#include <Alepha/IOStreams/String.h>
+
+static auto init= Alepha::Utility::enroll <=[]
+{
+	using namespace Alepha::literals::enum_literals;
+	using namespace Alepha::Testing::literals;
+
+	using namespace Alepha::Testing::exports;
+
+	using MyEnum= Alepha::Enum< "Adam"_value, "Baker"_value, "Charlie"_value, "David"_value >;
+
+	"Enum round trip printing test"_test <= TableTest
+	<
+		[]( const std::string s ) -> std::string
+		{
+			MyEnum e;
+			std::istringstream iss{ s };
+
+			( iss >> e );
+			return Alepha::IOStreams::String{} << e;
+		}
+	>
+	::Cases
+	{
+		{ "Adam", { "Adam" }, "Adam" },
+		{ "Charlie", { "Charlie" }, "Charlie" },
+		{ "Wrong", { "Wrong" }, std::type_identity< Alepha::EnumTextMismatchError >{} },
+	};
+
+	"Enum failure parse"_test <= TableTest
+	<
+		[]( const std::string s )
+		{
+			try
+			{
+				MyEnum e;
+				std::istringstream iss{ s };
+
+				( iss >> e );
+				throw "Fail";
+			}
+			catch( const Alepha::EnumTextMismatchError &ex )
+			{
+				return ex.expectedValues();
+			}
+		}
+	>
+	::Cases
+	{
+		{ "Wrong", { "Wrong" }, { "Adam", "Baker", "Charlie", "David" } },
+	};
+};

Enum.test/CMakeLists.txt

@@ -0,0 +1 @@
+unit_test( 0 )