private ITripleExpression Atomic()
{
GetNext();
ITripleExpression ret;
switch (current)
{
case State.number:
ret = new Const(constant);
GetNext();
break;
case State.variable:
ret = new Variable(Char.ToString(variable));
GetNext();
break;
case State.minus:
ret = new Subtract(new Const(0), Atomic());
break;
case State.abs:
ret = new Abs(Atomic());
break;
case State.square:
ret = new Square(Atomic());
break;
case State.lparen:
ret = Shifts();
if (current != State.rparen)
{
Console.WriteLine(") missing");
throw new InvalidOperationException(") missing");
}
GetNext();
break;
default:
ret = null;
Console.WriteLine("Unrecognizable format");
throw new InvalidOperationException("Unrecognizable format");
break;
}
return(ret);
}
private ITripleExpression <T> Atomic()
{
GetNext();
ITripleExpression <T> ret;
switch (current)
{
case State.number:
ret = new Const <T>(constant);
GetNext();
break;
case State.variable:
ret = new Variable <T>(Char.ToString(variable));
GetNext();
break;
case State.minus:
ret = new Negate <T>(Atomic(), op);
break;
case State.abs:
ret = new Abs <T>(Atomic(), op);
break;
case State.square:
ret = new Square <T>(Atomic(), op);
break;
case State.lparen:
ret = AddSubt();
GetNext();
break;
default:
ret = null;
throw new ParsingException("unrecognizable format");
}
return(ret);
}