code: func (m LiteralMap) Convert() (map[string]*Value, error) {
  	ret := make(map[string]*Value, len(m))
  	for k, v := range m {
  		v, err := NewValue(v)
  		if err != nil {
  			return nil, fmt.Errorf("key %q: %s", k, err)
  		}
  		ret[k] = v
  	}
  	return ret, nil
  }
docs: // Convert converts this to a parameter map that can be used with
  // Template.Render.