code: func (a *AttributeDefinition) AllNonZero() []string {
  	nzs := make([]string, len(a.NonZeroAttributes))
  	i := 0
  	for n := range a.NonZeroAttributes {
  		nzs[i] = n
  		i++
  	}
  	return nzs
  }
docs: // AllNonZero returns the complete list of all non-zero attribute name.