public static List<object> PairToList(Pair l)
{
List<object> r = new List<object>();
while (l != null) {
r.Add(l.Car);
l = (Pair)l.Cdr;
}
return r;
}
public static Pair ListToPair(List<object> l)
{
Pair r = null;
for (int i = l.Count - 1; i >= 0; --i) {
r = new Pair() {
Car = l[i], Cdr = r
};
}
return r;
}
private ByteCodeInterpreter()
{
Utils.QueryPerformanceCounter(out mTimerStart);
Utils.QueryPerformanceFrequency(out mTimerFreq);
Dictionary<string, object> builtinVars = new Dictionary<string, object>() {
{"true", true},
{"false", false},
{"else", true},
{"null", null},
};
Dictionary<string, HostProcedure> builtinProcedures = new Dictionary<string, HostProcedure>() {
{"not", (stack, ret) => stack[ret]=!(bool)stack[ret+1]},
{"identity", (stack, ret) => stack[ret]=stack[ret+1]},
{"sqr", (stack, ret) => {var a = (INumber)stack[ret+1]; stack[ret]=a.Mul(a);} },
{"+", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Add((INumber)stack[ret+2])},
{"-", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Sub((INumber)stack[ret+2])},
{"*", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Mul((INumber)stack[ret+2])},
{"/", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Div((INumber)stack[ret+2])},
{"quotient", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Div((INumber)stack[ret+2]).CastToInteger()},
{"remainder", (stack, ret) => stack[ret]=((INumber)stack[ret+1]).Mod((INumber)stack[ret+2])},
{"=", (stack, ret) => stack[ret]=stack[ret+1].Equals(stack[ret+2])},
{"<", (stack, ret) => stack[ret]=(stack[ret+1] as IComparable).CompareTo(stack[ret+2]) < 0},
{"<=", (stack, ret) => stack[ret]=(stack[ret+1] as IComparable).CompareTo(stack[ret+2]) <= 0},
{">", (stack, ret) => stack[ret]=(stack[ret+1] as IComparable).CompareTo(stack[ret+2]) > 0},
{">=", (stack, ret) => stack[ret]=(stack[ret+1] as IComparable).CompareTo(stack[ret+2]) >= 0},
{"eq?", (stack, ret) => stack[ret]=object.ReferenceEquals(stack[ret+1], stack[ret+2])},
{"cons", (stack, ret) => stack[ret]=new Pair() { Car = stack[ret+1], Cdr = stack[ret+2] }},
{"car", (stack, ret) => stack[ret]=((Pair)stack[ret+1]).Car},
{"cdr", (stack, ret) => stack[ret]=((Pair)stack[ret+1]).Cdr},
{"drop", (stack, ret) => {
Pair l = (Pair)stack[ret+1]; int n = ((NumberInteger)stack[ret+2]).value;
for (; n > 0; --n) {
l = (Pair)l.Cdr;
}
stack[ret] = l;
}},
{"length", (stack, ret) => {
int n = 0;
for (Pair l = (Pair)stack[ret+1]; l != null; ++n, l = (Pair)l.Cdr) ;
stack[ret] = Number.Create(n);
}},
{"append", (stack, ret) => {
var l = ListProcess.PairToList((Pair)stack[ret+1]);
l.InsertRange(l.Count, ListProcess.PairToList((Pair)stack[ret+2]));
stack[ret] = ListProcess.ListToPair(l);
}},
{"empty?", (stack, ret) => stack[ret]=stack[ret+1] == null},
{"pretty-print", (stack, ret) => {
ListProcess.PrintPairExp(stack[ret+1]);
stack[ret] = null;
}},
{"display", (stack, ret) => {
ListProcess.PrintListExp(ListProcess.PairExpToListExp(stack[ret+1]));
stack[ret] = null;
}},
{"current-inexact-milliseconds", (stack, ret) => {
long now;
Utils.QueryPerformanceCounter(out now);
stack[ret] = Number.Create((decimal)(now - mTimerStart) * 1000 / mTimerFreq);
}},
{"exit", (stack, ret) => {
Environment.Exit(0);
stack[ret] = null;
}},
{"random", (stack, ret) => stack[ret] = Number.Create(mRandom.Next(((NumberInteger)stack[ret+1]).value))},
{"eval", (stack, ret) => stack[ret] = Interpret(ListProcess.PairExpToListExp(stack[ret+1]))},
};
GlobalEnv.Instance().ReserveVariables(builtinVars.Count + builtinProcedures.Count);
foreach (KeyValuePair<string, object> kv in builtinVars) {
GlobalEnv.Instance().variables[SymbolTable.DefineOrGetGlobalSymbol(kv.Key).index] = kv.Value;
}
foreach (KeyValuePair<string, HostProcedure> kv in builtinProcedures) {
GlobalEnv.Instance().variables[SymbolTable.DefineOrGetGlobalSymbol(kv.Key).index] = kv.Value;
}
}
