code: func (s *Signature) similar(r *Signature, similar Similarity) bool {
  	if s.State != r.State || !s.CreatedBy.similar(&r.CreatedBy, similar) {
  		return false
  	}
  	if similar == ExactFlags && s.Locked != r.Locked {
  		return false
  	}
  	return s.Stack.similar(&r.Stack, similar)
  }
docs: // similar returns true if the two Signature are equal or almost but not quite
  // equal.