Example #1
0
        public Interpreter()
        {
            this.GlobalEnv = new Environment();

            this.tokenizer = new Tokenizer();
            this.parser = new PairParser();
            this.evaluator = new Evaluator(this);
            this.macroEvaluator = new Evaluator(this);
            this.macroExpander = new MacroExpander(macroEvaluator);

            DefinePrimitives();
        }
Example #2
0
        public override IScheminType Execute(Environment env, Evaluator eval, ScheminPair args)
        {
            ScheminPort readFrom = eval.CurrentInputPort;

            if (args.Length > 0)
            {
                readFrom = (ScheminPort) args.Car;
            }

            Tokenizer t = new Tokenizer();
            PairParser p = new PairParser();

            bool completeInput = false;
            bool emptyInput = true;
            int openParens = 0;
            int closeParens = 0;

            List<Token> partialInput = new List<Token>();

            while (completeInput != true)
            {
                StringBuilder built = new StringBuilder();
                char next;
                for (;;)
                {
                    int nextRead = readFrom.InputStream.Read();
                    next = (char)nextRead;

                    if (nextRead == -1 || (next == '\n' && !emptyInput))
                    {
                        break;
                    }

                    if (next != '\r')
                    {
                        built.Append(next);
                        emptyInput = false;
                    }
                }

                var lineTokens = t.Tokenize(built.ToString());

                foreach (Token token in lineTokens)
                {
                    partialInput.Add(token);
                    if (token.Type == TokenType.OpenParen)
                    {
                        openParens++;
                    }
                    else if (token.Type == TokenType.CloseParen)
                    {
                        closeParens++;
                    }
                }

                if (openParens == closeParens)
                {
                    completeInput = true;
                    break;
                }
            }

            var parsed = p.Parse(partialInput, true).Car;

            return parsed;
        }