void AssignUniqueIds(Exercise content, ref int cnt) { if (content is EvalExercise) ((EvalExercise)content).Id = cnt++; foreach (Exercise ex in content.SubExercises) AssignUniqueIds(ex, ref cnt); }
void AssignOwners(Exercise ex, Exercise owner) {
ex.Owner = owner; ex.Expand();
foreach (Exercise subex in ex.SubExercises) AssignOwners(subex, ex);
}
protected static IEnumerable<Exercise> getSubExcs(Exercise[] excs) { return excs == null ? Enumerable.Empty<Exercise>() : excs; }
protected static Exercise[] expandHelper(Exercise[] excs) {
if (excs == null || !excs.Any(e => e is IExpandable)) return excs;
List<Exercise> res = new List<Exercise>();
foreach (Exercise ex in excs)
if (ex is IExpandable) res.AddRange(((IExpandable)ex).Expand()); else res.Add(ex);
return res.ToArray();
}
public static Exercise expandHelper(Exercise by) {
if (by == null || !(by is IExpandable)) return by;
return ((IExpandable)by).Expand().SingleOrDefault();
}