public override object VisitQuantifiedSentence(QuantifiedSentence sentence, object arg)
{
var substitution = (IDictionary <Variable, ITerm>)arg;
var quantified = sentence.Quantified;
var quantifiedAfterSubs = (ISentence)quantified.Accept(this, arg);
var variables = new List <Variable>();
foreach (Variable v in sentence.Variables)
{
if (substitution.ContainsKey(v))
{
ITerm st = substitution[v];
if (st is Variable)
{
// Only if it is a variable to I replace it, otherwise
// I drop it.
variables.Add((Variable)st.Copy());
}
}
else
{
// No substitution for the quantified variable, so
// keep it.
variables.Add((Variable)v.Copy());
}
}
// If not variables remaining on the quantifier, then drop it
if (variables.Count == 0)
{
return(quantifiedAfterSubs);
}
return(new QuantifiedSentence(sentence.Quantifier, variables, quantifiedAfterSubs));
}