Ejemplo n.º 1
0
        static object ListToString(object list)
        {
            string outStr = "";

            while (list != null)
            {
                outStr += (char)Cons.Car(list);
                list    = Cons.Cdr(list);
            }
            return(outStr);
        }
Ejemplo n.º 2
0
        object RunClosure(Closure closure, params object[] args)
        {
            var prevCONT      = _cont;
            var prevENVT      = _envt;
            var prevEvalStack = _evalStack;
            var prevTEMPLATE  = _template;
            var prevPC        = _pc;

            _cont      = null;
            _envt      = closure.Envt;
            _evalStack = Cons.Reverse(Cons.ConsFromArray(args));
            _template  = closure.Template;
            _pc        = 0;
            _value     = Void.TheVoidValue;

            try {
                while (true)
                {
                    var i = _template.Code[_pc];
                    switch (i.OpCode)
                    {
                    case Instruction.OpCodes.Push:
                        _evalStack = new Cons(_value, _evalStack);
                        _pc++;
                        break;

                    case Instruction.OpCodes.Bind: {
                        var numOfBindings = (int)i.AX;
                        _envt = new LexicalEnvironment(_envt, numOfBindings);
                        for (var x = 0; x < numOfBindings; x++)
                        {
                            _envt.Bindings[numOfBindings - 1 - x] = Cons.Car(_evalStack);
                            _evalStack = Cons.Cdr(_evalStack);
                        }
                        if (_evalStack != null)
                        {
                            throw new InvalidOperationException("Too many parameters given to function");
                        }
                        _pc++;
                    }
                    break;

                    case Instruction.OpCodes.ToplevelGet:
                        _value = ToplevelLookup(_value as Symbol);
                        _pc++;
                        break;

                    case Instruction.OpCodes.SaveContinuation:
                        _cont      = new Continuation(_cont, _envt, _evalStack, _template, i.AX);
                        _evalStack = null;
                        _pc++;
                        break;

                    case Instruction.OpCodes.FetchLiteral:
                        _value = _template.Literals[i.AX];
                        _pc++;
                        break;

                    case Instruction.OpCodes.LocalGet: {
                        LexicalEnvironment envt = _envt;
                        for (int x = 0; x < i.A; x++)
                        {
                            envt = envt.Parent;
                        }
                        _value = envt.Bindings[i.B];
                        _pc++;
                    }
                    break;

                    case Instruction.OpCodes.JumpIfFalse: {
                        if (_value is bool && ((bool)_value == false))
                        {
                            _pc = i.AX;
                        }
                        else
                        {
                            _pc++;
                        }
                    }
                    break;

                    case Instruction.OpCodes.BindVarArgs: {
                        var numOfBindings = (int)i.AX;
                        _envt = new LexicalEnvironment(_envt, numOfBindings);

                        // parameters are reversed on EVAL stack
                        _evalStack = Cons.Reverse(_evalStack);

                        for (var x = 0; x < numOfBindings; x++)
                        {
                            // if it is the last binding, take the rest of the EVAL_STACK
                            if (x == numOfBindings - 1)
                            {
                                _envt.Bindings[x] = _evalStack;
                                _evalStack        = null;
                            }
                            else
                            {
                                _envt.Bindings[x] = Cons.Car(_evalStack);
                                _evalStack        = Cons.Cdr(_evalStack);
                            }
                        }
                        _pc++;
                    }
                    break;

                    case Instruction.OpCodes.MakeClosure:
                        _value = new Closure(_envt, _value as Template);
                        _pc++;
                        break;

                    case Instruction.OpCodes.Return:
                        Return();
                        break;

                    case Instruction.OpCodes.ToplevelSet:
                        _toplevelEnv[_value as Symbol] = Cons.Car(_evalStack);
                        _evalStack = Cons.Cdr(_evalStack);
                        _pc++;
                        break;

                    case Instruction.OpCodes.Apply: {
                        if (_value is Closure)
                        {
                            var clos = _value as Closure;
                            _envt     = clos.Envt;
                            _template = clos.Template;
                            _value    = Void.TheVoidValue;
                            _pc       = 0;
                        }
                        else if (_value is Func <object> )
                        {
                            var func = _value as Func <object>;
                            _value = func();
                            Return();
                        }
                        else if (_value is Func <object, object> )
                        {
                            var func = _value as Func <object, object>;
                            _value = func(Cons.Car(_evalStack));
                            Return();
                        }
                        else if (_value is Func <object, object, object> )
                        {
                            var func = _value as Func <object, object, object>;
                            _value = func(Cons.Car(Cons.Cdr(_evalStack)), Cons.Car(_evalStack));
                            Return();
                        }
                        else if (_value is Func <object, object, object, object> )
                        {
                            var func = _value as Func <object, object, object, object>;
                            _value = func(Cons.Car(Cons.Cdr(Cons.Cdr(_evalStack))), Cons.Car(Cons.Cdr(_evalStack)), Cons.Car(_evalStack));
                            Return();
                        }
                        else if (_value is Func <object, object, object, object, object> )
                        {
                            var func = _value as Func <object, object, object, object, object>;
                            _value = func(Cons.Car(Cons.Cdr(Cons.Cdr(Cons.Cdr(_evalStack)))), Cons.Car(Cons.Cdr(Cons.Cdr(_evalStack))), Cons.Car(Cons.Cdr(_evalStack)), Cons.Car(_evalStack));
                            Return();
                        }
                        else if (_value is Func <object[], object> )
                        {
                            var func = _value as Func <object[], object>;
                            _value = func(Cons.ToReverseObjectArray(_evalStack));
                            Return();
                        }
                        else
                        {
                            throw new LunulaException("VALUE register does not contain a callable object: " + _value);
                        }
                    }
                    break;

                    case Instruction.OpCodes.LocalSet: {
                        var envt = _envt;
                        for (var x = 0; x < i.A; x++)
                        {
                            envt = envt.Parent;
                        }
                        envt.Bindings[i.B] = _value;
                        _pc++;
                    }
                    break;

                    case Instruction.OpCodes.Jump:
                        _pc = i.AX;
                        break;

                    case Instruction.OpCodes.End:
                        _finished = true;
                        break;

                    default:
                        throw new InvalidOperationException("Invalid instruction");
                    }
                    if (_finished)
                    {
                        _finished = false;
                        return(_value);
                    }
                }
            } finally {
                _cont      = prevCONT;
                _envt      = prevENVT;
                _evalStack = prevEvalStack;
                _template  = prevTEMPLATE;
                _pc        = prevPC;
            }
        }
Ejemplo n.º 3
0
 static object Cdr(object cons)
 {
     return(Cons.Cdr(cons));
 }