Pytocs.Syntax.Parser.except_clause C# (CSharp) Method

        public AliasedExp except_clause()
        {
            var token = Expect(TokenType.Except);
            var posStart = token.Start;
            var posEnd = token.End;
            Exp t = null;
            Identifier alias = null;
            if (!Peek(TokenType.COLON))
            {
                t = test();
                posEnd = t.End;
                if (PeekAndDiscard(TokenType.As))
                {
                    alias = id();
                    posEnd = alias.End;
                }
                else if (PeekAndDiscard(TokenType.COMMA))
                {
                    alias = id();
                    posEnd = token.End;
                }
            }
            return new AliasedExp(t, alias, filename, posStart, posEnd);
        }