private void CreateConnective(char connective)
{
Proposition result = null;
// 'GetCorrespondingConnective'
switch (connective)
{
case Negation.SYMBOL:
result = new Negation();
break;
case Implication.SYMBOL:
result = new Implication();
break;
case BiImplication.SYMBOL:
result = new BiImplication();
break;
case Conjunction.SYMBOL:
result = new Conjunction();
break;
case Disjunction.SYMBOL:
result = new Disjunction();
break;
case Nand.SYMBOL:
result = new Nand();
break;
case UniversalQuantifier.SYMBOL:
result = new UniversalQuantifier(PopBoundVariable());
break;
case ExistentialQuantifier.SYMBOL:
result = new ExistentialQuantifier(PopBoundVariable());
break;
}
// 'CreateExpression'
// The symbols[symbols.Count - 1] can always be done. Placement is dependent on Unary or Binary connective.
if (result is BinaryConnective)
{
((BinaryConnective)result).LeftSuccessor = symbols[symbols.Count - 2];
((BinaryConnective)result).RightSuccessor = symbols[symbols.Count - 1];
symbols.RemoveAt(symbols.Count - 1);
symbols.RemoveAt(symbols.Count - 1);
}
else
{
((UnaryConnective)result).LeftSuccessor = symbols[symbols.Count - 1];
symbols.RemoveAt(symbols.Count - 1);
}
// Now the expression is a symbol in case a nested connective needs to use it
// as right or left successor.
symbols.Add(result);
}
public override Proposition Copy()
{
Quantifier quantifier = null;
if (Data == UniversalQuantifier.SYMBOL)
{
quantifier = new UniversalQuantifier(boundVariable);
}
else
{
quantifier = new ExistentialQuantifier(boundVariable);
}
foreach (char appliedVariable in alreadyAppliedReplacementCharacters)
{
quantifier.AddAppliedReplacementVariable(appliedVariable);
}
quantifier.LeftSuccessor = LeftSuccessor.Copy();
return(quantifier);
}