Fix issue with std::function reflection on Windows.

Author: jjrv

include/nbind/TypeStd.h

@@ -42,7 +42,8 @@ template <int argCount>
 struct CallbackStructure {
 	const StructureType placeholderFlag;
 	const int arity;
-	const TYPEID argType[argCount + 1];
+	const TYPEID returnType;
+	const TYPEID argType[argCount];
 };
 
 template<typename ReturnType, typename... Args>
@@ -59,7 +60,7 @@ const CallbackStructure<sizeof...(Args)> Typer<std::function<ReturnType (Args...
 	StructureType :: callback,
 	sizeof...(Args),
 	Typer<ReturnType>::makeID(),
-	Typer<Args>::makeID()...
+	{ Typer<Args>::makeID()... }
 };
 
 } // namespace

src/reflect.cc

@@ -139,7 +139,7 @@ External NBind :: queryType(
 
 		case StructureType :: callback:
 			callbackSpec = static_cast<const CallbackStructure<1> *>(id.getStructure());
-			rawTypePtr = callbackSpec->argType + 1;
+			rawTypePtr = callbackSpec->argType;
 			arity = callbackSpec->arity;
 
 			while(arity--) {
@@ -149,7 +149,7 @@ External NBind :: queryType(
 
 			result = outTypeDetail.call<External>(
 				static_cast<unsigned char>(placeholderFlag),
-				NBindID(callbackSpec->argType[0]),
+				NBindID(callbackSpec->returnType),
 				typeIdList
 			);