private static void Define(Evaluator eval, StackFrame frame)
{
var(sym, value, context) = StructureUtils.Split3(frame.args);
if (sym.type != AtomType.Symbol)
{
throw new ArgumentException("Definition name must be symbol!");
}
if (eval.HaveReturn())
{
string name = (string)sym.value;
Atom result = eval.TakeReturn();
Context ctx = context?.value as Context ?? frame.context.value as Context;
if (result?.value is Closure function)
{
function.Name = name;
}
//Console.WriteLine($"DEFINE: '{name}' = '{result}' at -internal-state-{ctx}");
ContextUtils.Define(ctx, result, name);
eval.Return(result);
return;
}
eval.CreateFrame("-eval-", value, frame.context);
frame.state = Atoms.INTERNAL_STATE;
}
private static void Undefine(Evaluator eval, StackFrame frame)
{
var args = frame.args;
Atom sym = (Atom)args?.value;
if (sym.type != AtomType.Symbol)
{
throw new ArgumentException("Undefining name must be symbol!");
}
var ctx = frame.context.value as Context;
var result = ContextUtils.Undefine(ctx, (string)sym.value);
eval.Return(result);
}
private static void TableImportAll(Evaluator eval, StackFrame frame)
{
var(src, dst) = StructureUtils.Split2(frame.args);
if (dst == null || dst.IsPair)
{
dst = frame.context.atom;
}
var srcCtx = GetDictionary(src);
var dstCtx = GetDictionary(dst);
ContextUtils.ImportAllSymbols(srcCtx, dstCtx);
eval.Return(null);
}
private static void TableImport(Evaluator eval, StackFrame frame)
{
var(src, dst, names) = StructureUtils.Split3(frame.args);
if (names == null && dst.IsPair)
{
names = dst;
dst = frame.context.atom;
}
var srcCtx = GetDictionary(src);
var dstCtx = GetDictionary(dst);
string[] nameList = StructureUtils.ListToStringArray(names, "TABLE");
ContextUtils.ImportSymbols(srcCtx, dstCtx, nameList);
eval.Return(null);
}
private static void SetFirst(Evaluator eval, StackFrame frame)
{
var args = frame.args;
Atom sym = (Atom)args?.value;
if (sym.type != AtomType.Symbol)
{
throw new ArgumentException("Variable name must be symbol!");
}
if (eval.HaveReturn())
{
var result = eval.TakeReturn();
var ctx = frame.context.value as Context;
ContextUtils.Set(ctx, result, (string)sym.value);
eval.Return(result);
return;
}
eval.CreateFrame("-eval-", args.next?.atom, frame.context);
frame.state = Atoms.INTERNAL_STATE;
}
public Atom Evaluate(Atom atom, Context current_context, string startState = null)
{
_retValue = null;
_haveReturn = false;
Stack.CreateFrame(startState ?? "-eval-", atom, current_context);
Console.WriteLine("Start evaluation");
while (Stack.stack.Count > 0)
{
if (ErrorMessage != null)
{
Console.WriteLine($"[ERROR] {ErrorMessage}");
ErrorMessage = null;
return(null);
}
// Console.WriteLine($"RetValue: {_retValue}");
// Stack.Dump(1);
//Thread.Sleep(50);
Function func;
StackFrame frame = Stack.TopFrame;
switch (frame.state.value)
{
case "-eval-":
if (frame.expression.IsPair)
{
frame.state = new Atom("-eval-sexp-head-");
continue;
}
if (frame.expression.IsSymbol)
{
var name = (string)frame.expression.value;
try
{
SetReturn(ContextUtils.Get((Context)frame.context.value, name));
}
catch (BombardoException e)
{
Console.WriteLine($"[ERROR] {e}");
return(null);
}
CloseFrame();
continue;
}
SetReturn(frame.expression);
CloseFrame();
continue;
case "-eval-each-":
if (HaveReturn())
{
frame.temp1 = StructureUtils.BuildListContainer(frame.temp1, TakeReturn());
}
if (frame.expression != null)
{
var subExpression = frame.expression.atom;
frame.expression = frame.expression.next;
Stack.CreateFrame("-eval-", subExpression, frame.context);
continue;
}
SetReturn(frame.temp1.atom);
// frame.temp1 = null;
CloseFrame();
continue;
case "-eval-block-":
if (HaveReturn())
{
frame.temp1 = TakeReturn();
}
if (frame.expression != null)
{
var subExpression = frame.expression.atom;
frame.expression = frame.expression.next;
Stack.CreateFrame("-eval-", subExpression, frame.context);
continue;
}
SetReturn(frame.temp1);
// frame.temp1 = null;
CloseFrame();
continue;
case "-eval-sexp-head-":
if (!HaveReturn())
{
var head = frame.expression.atom;
Stack.CreateFrame("-eval-", head, frame.context);
continue;
}
frame.function = TakeReturn();
if (!frame.function.IsFunction)
{
Console.WriteLine($"[ERROR] Head is not function: {frame.function}");
return(null);
}
frame.state = new Atom("-eval-sexp-args-");
continue;
case "-eval-sexp-args-":
if (!HaveReturn())
{
func = (Function)frame.function.value;
if (func.EvalArgs && frame.expression.next != null)
{
Stack.CreateFrame("-eval-each-", frame.expression.next, frame.context);
continue;
}
frame.args = frame.expression.next;
frame.state = new Atom("-eval-sexp-body-");
continue;
}
frame.args = TakeReturn();
frame.state = new Atom("-eval-sexp-body-");
continue;
case "-eval-sexp-body-":
func = (Function)frame.function.value;
if (!HaveReturn())
{
func.Apply(this, frame);
continue;
}
if (func.EvalResult)
{
frame.state = new Atom("-eval-sexp-result-");
frame.temp1 = TakeReturn();
continue;
}
CloseFrame();
continue;
case "-eval-sexp-result-":
if (!HaveReturn())
{
Stack.CreateFrame("-eval-", frame.temp1, frame.context);
continue;
}
SetReturn(frame.temp1);
frame.temp1 = null;
CloseFrame();
continue;
}
// Ни один из указанных стейтов, значит:
// Либо это стейты функции и тогда её надо вызывать
if (frame.function != null)
{
func = (Function)frame.function.value;
func.Apply(this, frame);
continue;
}
// Либо если нет функции - то это ошибка интерпретации
SetError($"Wrong evaluation state: {frame.state.value}");
}
if (HaveReturn())
{
return(TakeReturn());
}
return(null);
}