private static void AddElementsFor(this IList<string> alphabet, LTLFormula formula)
{
var traversal = new ExtractAlphabet (formula);
foreach (var element in traversal.Alphabet)
if (!alphabet.Contains (element))
alphabet.Add (element);
}
public void TestBug2()
{
var formula = Parser.Parse ("G (a -> a U b) & G (b -> b U a)");
Assert.IsNotNull (formula);
var v = new ExtractAlphabet (formula);
var alphabet = v.Alphabet;
Assert.AreEqual (2, alphabet.Count);
}