/// <summary>
/// Traverses the list to perform operations on items according to operator precedence
/// </summary>
/// <returns>final evaluated expression of Expression string</returns>
private object EvaluateList()
{
ArrayList list = (ArrayList)_expressionlist.Clone();
//Do the unary operators first
for (int x = 0; x < list.Count; x++)
{
if (list[x] is UnaryOp)
{
list[x] = PerformUnaryOp(
(UnaryOp)list[x],
list[x + 1]
);
list.RemoveAt(x + 1);
}
}
//Get the queued binary operations
BinaryOpQueue opqueue = new BinaryOpQueue(list);
string msg = "";
for (int x = 1; x < list.Count; x += 2)
{
bool bError = false;
if (list[x] is BinaryOp)
{
if (x + 1 == list.Count)
{
throw new ArgumentException(
"Expression cannot end in a binary operation: [" + list[x].ToString() + "]"
);
}
}
else
{
msg += string.Format(
"\n{0} [?] {1}",
(list[x - 1] is string) ? "\"" + list[x - 1] + "\"" : list[x - 1],
(list[x] is string) ? "\"" + list[x] + "\"" : list[x]
);
x--;
}
}
if (msg != "")
throw new ArgumentException("Missing binary operator: " + msg);
BinaryOp op = opqueue.Dequeue();
while (op != null)
{
int nIdx = list.IndexOf(op);
list[nIdx - 1] = PerformBinaryOp(
(BinaryOp)list[nIdx],
list[nIdx - 1],
list[nIdx + 1]
);
list.RemoveAt(nIdx);
list.RemoveAt(nIdx);
op = opqueue.Dequeue();
}
object ret = null;
if (list[0] is IExpression)
ret = ((IExpression)list[0]).Evaluate();
else
ret = list[0];
return ret;
}
/// <summary>
/// Traverses the list to perform operations on items according to operator precedence
/// </summary>
/// <returns>final evaluated expression of Expression string</returns>
private object EvaluateList()
{
ArrayList list = (ArrayList)_expressionlist.Clone();
//Do the unary operators first
for (int x = 0; x < list.Count; x++)
{
if (list[x] is UnaryOp)
{
list[x] = PerformUnaryOp(
(UnaryOp)list[x],
list[x + 1]
);
list.RemoveAt(x + 1);
}
}
//Get the queued binary operations
BinaryOpQueue opqueue = new BinaryOpQueue(list);
string msg = "";
for (int x = 1; x < list.Count; x += 2)
{
if (list[x] is BinaryOp)
{
if (x + 1 == list.Count)
{
throw new ArgumentException(
"Expression cannot end in a binary operation: [" + list[x].ToString() + "]"
);
}
}
else
{
msg += string.Format(
"\n{0} [?] {1}",
(list[x - 1] is string) ? "\"" + list[x - 1] + "\"" : list[x - 1],
(list[x] is string) ? "\"" + list[x] + "\"" : list[x]
);
x--;
}
}
if (msg != "")
{
throw new ArgumentException("Missing binary operator: " + msg);
}
BinaryOp op = opqueue.Dequeue();
while (op != null)
{
int nIdx = list.IndexOf(op);
list[nIdx - 1] = PerformBinaryOp(
(BinaryOp)list[nIdx],
list[nIdx - 1],
list[nIdx + 1]
);
list.RemoveAt(nIdx);
list.RemoveAt(nIdx);
op = opqueue.Dequeue();
}
object ret = null;
if (list[0] is IExpression)
{
ret = ((IExpression)list[0]).Evaluate();
}
else
{
ret = list[0];
}
return(ret);
}
