public static void BeginEdit(this IEditableObject self)
{
// store current state to temporary storage
var state = self.GetPublicState();
object temp;
if (state.TryGetValue(SystemFields.Shapshot, out temp))
{
return; // idempotent
}
var deepClone = self is IComposite;
var clone = self.Clone(deepClone);
self.SetPropertyInternal(SystemFields.Shapshot, clone);
self.SetPropertyInternal(SystemFields.IsChanged, false);
}