private static void HandleSpecialCommand(IEvaluationContext context, string input)
{
switch (input.ToUpper())
{
case "$RAD":
context.DegreeMode = DegreesMode.Radians;
Console.WriteLine("Degree mode set to radians.");
break;
case "$DEG":
context.DegreeMode = DegreesMode.Degrees;
Console.WriteLine("Degree mode set to degrees.");
break;
case string set when set.StartsWith("$SET"):
Console.WriteLine($"Mode={context.DegreeMode}");
break;
case "$VAR":
foreach (var name in context.Variables)
{
Console.WriteLine($"{name}={context.GetVariableValue(name)}");
}
break;
case "$CONST":
foreach (var name in context.Constants)
{
Console.WriteLine($"{name}={context.GetVariableValue(name)}");
}
break;
case "$HELP":
Console.WriteLine("CalcX is a normal calculator, with support for functions and variables.");
Console.WriteLine("Meta commands start with '$': $rad, $deg, $var, $const, $set");
break;
default:
Console.WriteLine("Unknown directive. Enter $help for some help.");
break;
}
}
public double Calculate(IEnumerable <Token> tokens)
{
var stack = new Stack <double>(16);
foreach (var token in tokens)
{
switch (token)
{
case NumberToken n:
stack.Push(n.Value);
break;
case VariableToken v:
stack.Push(Context.GetVariableValue(v.Text));
break;
case OperatorToken op:
stack.Push(OperatorMap[op.Text].Eval(null, stack));
break;
case FunctionToken func:
var count = Context.GetFunctionArgumentCount(func.Text);
var args = new List <double>(count);
for (int i = 0; i < count; i++)
{
args.Add(stack.Pop());
}
stack.Push(Context.EvalFunction(func.Text, args.ToArray()));
break;
default:
throw new InvalidOperationException();
}
}
return(stack.Peek());
}