code: func (f *FwdDep) Edge() *FwdEdge {
  	ret := &FwdEdge{To: &f.Dependee, From: &dm.Attempt_ID{}}
  	if err := ret.From.SetDMEncoded(f.Depender.StringID()); err != nil {
  		panic(err)
  	}
  	return ret
  }
docs: // Edge produces a edge object which points 'forwards' from the depending
  // attempt to the depended-on attempt.