AIMA.Core.Logic.FOL.Unifier.unify C# (CSharp) Метод

        public Dictionary<Variable, Term> unify(List<FOLNode> x,
                List<FOLNode> y, Dictionary<Variable, Term> theta)
        {
            if (theta == null)
            {
                return null;
            }
            else if (x.Count != y.Count)
            {
                return null;
            }
            else if (x.Count == 0 && y.Count == 0)
            {
                return theta;
            }
            else if (x.Count == 1 && y.Count == 1)
            {
                return unify(x[0], y[0], theta);
            }
            else
            {
                return unify(x.Skip(1).ToList<FOLNode>(), y.Skip(1).ToList<FOLNode>(), unify(
                        x[0], y[0], theta));
            }
        }