Boo.Lang.Compiler.Steps.ProcessMethodBodies.OnExceptionHandler C# (CSharp) Метод

        public override void OnExceptionHandler(ExceptionHandler node)
        {
            bool untypedException = (node.Flags & ExceptionHandlerFlags.Untyped) == ExceptionHandlerFlags.Untyped;
            bool anonymousException = (node.Flags & ExceptionHandlerFlags.Anonymous) == ExceptionHandlerFlags.Anonymous;
            bool filterHandler = (node.Flags & ExceptionHandlerFlags.Filter) == ExceptionHandlerFlags.Filter;

            if (untypedException)
            {
                // If untyped, set the handler to except System.Exception
                node.Declaration.Type = CodeBuilder.CreateTypeReference(TypeSystemServices.ExceptionType);
            }
            else
            {
                Visit(node.Declaration.Type);

                // Require typed exception handlers to except only
                // exceptions at least as derived as System.Exception
                if(!TypeSystemServices.IsValidException(GetType(node.Declaration.Type)))
                {
                    Errors.Add(CompilerErrorFactory.InvalidExceptArgument(node.Declaration.Type, GetType(node.Declaration.Type)));
                }
            }

            if(!anonymousException)
            {
                // If the exception is not anonymous, place it into a
                // local variable and enter a new namespace
                DeclareLocal(node.Declaration, true);
                EnterNamespace(new DeclarationsNamespace(CurrentNamespace, node.Declaration));
            }

            try
            {
                // The filter handler has access to the exception if it
                // is not anonymous, so it is protected to ensure
                // any exception in the filter condition (a big no-no)
                // will still clean up the namespace if necessary
                if (filterHandler)
                {
                    Visit(node.FilterCondition);
                }

                Visit(node.Block);
            }
            finally
            {
                // Clean up the namespace if necessary
                if(!anonymousException)
                {
                    LeaveNamespace();
                }
            }
        }