COMPILE_ASSERT XToString table sizes

pull out common XToString code
simplify XToString

stepmania/src/EnumHelper.cpp

@@ -31,6 +31,27 @@ int CheckEnum( lua_State *L, LuaReference &table, int iPos, int iInvalid, const
 	return iRet;
 }
 
+// szNameArray is of size iMax; pNameCache is of size iMax+2.
+const RString &EnumToString( int iVal, int iMax, const char **szNameArray, auto_ptr<RString> *pNameCache )
+{
+	if( unlikely(pNameCache[0].get() == NULL) )
+	{
+		for( int i = 0; i < iMax; ++i )
+		{
+			auto_ptr<RString> ap( new RString( szNameArray[i] ) );
+			pNameCache[i] = ap;
+		}
+
+		auto_ptr<RString> ap( new RString );
+		pNameCache[iMax+1] = ap;
+	}
+
+	// iMax+1 is "Invalid".  iMax+0 is the NUM_ size value, which can not be converted
+	// to a string.
+	ASSERT_M( iVal >= 0 && (iVal < iMax || iVal == iMax+1), ssprintf("%i, %i", iVal, iMax)  );
+	return *pNameCache[iVal];
+}
+
 /*
  * (c) 2004 Chris Danford
  * All rights reserved.

stepmania/src/EnumHelper.h

@@ -80,28 +80,15 @@ namespace Enum
 };
 
 static const RString EMPTY_STRING;
+const RString &EnumToString( int iVal, int iMax, const char **szNameArray, auto_ptr<RString> *pNameCache ); // XToString helper
 
-// TypeName[] must be an array of const char *, not RString, to
+#define XToString(X, CNT) \
-// avoid initialization order problems when calling XToString.
-// Use Check##X##ToStringParamType to enforce that.
-#define XToString(X, CNT)	\
 	static void Check##X##ToStringParamType( const char **p ) { } \
+	COMPILE_ASSERT( NUM_##X == ARRAYLEN(X##Names) ); \
 	const RString& X##ToString( X x ) \
 	{	\
-		Check##X##ToStringParamType( X##Names ); \
+		static auto_ptr<RString> as_##X##Name[NUM_##X+2]; \
-		static auto_ptr<RString> as_##X##Name[NUM_##X]; \
+		return EnumToString( x, NUM_##X, X##Names, as_##X##Name ); \
-		if( as_##X##Name[0].get() == NULL ) { \
-			for( unsigned i = 0; i < NUM_##X; ++i ) \
-			{ \
-				auto_ptr<RString> ap( new RString( X##Names[i] ) ); \
-				as_##X##Name[i] = ap; \
-			} \
-		} \
-		ASSERT( NUM_##X == ARRAYLEN(X##Names) );	\
-		if( x == NUM_##X+1 ) 	\
-			return EMPTY_STRING;	\
-		ASSERT( x < NUM_##X );	\
-		return *as_##X##Name[x];	\
 	}
 
 #define XToLocalizedString(X)      \