private void Hold(SymbolToken val)
{
_heldInput.Add(val);
if (val.Type == SymbolType.OpenBracket)
{
_parentheses++;
}
if (val.Type == SymbolType.CloseBracket)
{
_parentheses--;
}
if (_parentheses == 0)
{
// Remove all surrounding parentheses
while (_heldInput.HasRedundantParentheses())
{
if (_heldInput.Count == 2)
{
var close = _heldInput[_heldInput.Count - 1];
throw new InvalidParenthesisException(close.Position);
}
_heldInput = _heldInput.GetRange(1, _heldInput.Count - 2);
}
var pp = new RedundantParenthesesProcessor(_heldInput);
var output = pp.PumpAll();
// Decide if parentheses should be added back in
if (output.Count == 1 && !_lastOutput.Type.IsUnaryOperation())
{
Output(output);
}
else
{
Output(SymbolToken.OpenBracket);
Output(output);
Output(SymbolToken.CloseBracket);
}
_heldInput = new List <SymbolToken>();
_holdInput = false;
}
}
