public abstract HashSet <Triple <T1, T2, T3> > getPullback(
BetterName <T1, T2> fi,
HashSet <T1> domfi,
BetterName <T3, T2> gi,
HashSet <T3> domgi,
HashSet <T2> codomi,
Func <T2, T2, bool> comp);
//public override HashSet<Triple<Product, string, Article>> getPullback(
// BetterName<Product, string> fi,
// HashSet<string> domfi,
// BetterName<Article, string> gi,
// HashSet<string> domgi,
// HashSet<string> codomi,
// Func<string, string, bool> comp)
//{
// var results = new HashSet<Triple<Product, String, Article>>();
// if (domfi.Count > domgi.Count)
// {
// foreach (var x in domfi)
// {
// foreach (var y in domgi)
// {
// var rezX = fi.Compute(x);
// var rezY = gi.Compute(y);
// if (comp(rezY, rezX))
// {
// results.Add(new Triple<Product, string, Article>() {x = x, z = rezY, y = y});
// }
// }
// }
// }
// else
// {
// foreach (var y in domgi)
// {
// foreach (var x in domfi)
// {
// var rezX = fi.Compute(x);
// var rezY = gi.Compute(y);
// if (comp(rezY, rezX))
// {
// results.Add(new Triple<Product, string, Artic>() { x = x, z = rezY, y = y });
// }
// }
// }
// }
// return results;
//}
public override HashSet <Triple <Product, string, Article> > getPullback(BetterName <Product, string> fi, HashSet <Product> domfi, BetterName <Article, string> gi, HashSet <Article> domgi, HashSet <string> codomi, Func <string, string, bool> comp)
{
throw new NotImplementedException();
}