private static void Command(ListController <TokenModel> lc)
{
if (lc.TryGetNext(out var first))
{
if (Keywords.Types.Contains(first.Text))
{
var varType = first.Text;
string varName = Variable(lc);
VarTable.Add(varName, varType);
}
else if (VarTable.Contains(first.Text))
{
if (!lc.TryGetNext(out var eq))
{
throw new ParseException("= expected", lc.GetPrevious(), true);
}
if (eq.Text != "=")
{
throw new ParseException("= expected", lc.GetPrevious(), true);
}
AssingNode asNode = new AssingNode();
asNode.Left = new VarNode()
{
Variable = VarTable.Get(first.Text),
};
if (!lc.TryGetNext(out var next))
{
throw new ParseException("Function or expression expected", lc.GetPrevious(), true);
}
if (FuncTable.Contains(next.Text))
{
lc.SetBack();
asNode.Right = Func(lc);
}
else if (VarTable.Contains(next.Text) || next.Text.All(c => Constants.Numbers.Contains(c)))
{
lc.SetBack();
//todo arithmetic
throw new NotImplementedException("Arithmetic don't included, for now");
}
else
{
throw new ParseException("Function or expression expected", lc.GetPrevious(), true);
}
}
}
}
public static TokenModel TryGetNext(ListController <TokenModel> lc, string errorMessage)
{
if (lc.TryGetNext(out var ret))
{
return(ret);
}
throw new ParseException(errorMessage, lc.GetPrevious(), true);
}
private static FunctionNode Func(ListController <TokenModel> lc)
{
if (!lc.TryGetNext(out var funcName))
{
throw new ParseException("Function expected", lc.GetPrevious(), true);
}
if (!FuncTable.Contains(funcName.Text))
{
throw new ParseException("Unknown function", lc.GetPrevious(), true);
}
var resNode = new FunctionNode();
resNode.FuncName = funcName.Text;
if (!lc.TryGetNext(out var opNest))
{
throw new ParseException();
}
else
{
if (opNest.Text == "(")
{
while (true)
{
if (lc.TryGetNext(out var next))
{
if (next.Text == ")")
{
break;
}
if ()
{
}
}
}
}
}
//todo parse tokens to node
}
public static void Lang(ListController <TokenModel> lc)
{
while (true)
{
Command(lc);
if (!lc.TryGetNext(out var sc))
{
throw new ParseException("; expected", lc.GetPrevious(), true);
}
if (sc.Text != ";")
{
throw new ParseException("; expected", lc.GetPrevious(), true);
}
if (!lc.TryGetNext(out _))
{
return;
}
lc.SetBack();
}
}
private static string Variable(ListController <TokenModel> lc)
{
if (!lc.TryGetNext(out var variable))
{
throw new ParseException("Variable name expected", lc.GetPrevious(), true);
}
if (!Constants.Alphabet.Contains(variable.Text[0]))
{
throw new ParseException($"Invalid token '{variable.Text[0]}' in variable name", variable);
}
return(variable.Text);
}
