code: func (s *Struct) FieldOk(name string) (*Field, bool) {
  	t := s.value.Type()
  
  	field, ok := t.FieldByName(name)
  	if !ok {
  		return nil, false
  	}
  
  	return &Field{
  		field:      field,
  		value:      s.value.FieldByName(name),
  		defaultTag: s.TagName,
  	}, true
  }
docs: // FieldOk returns a new Field struct that provides several high level functions
  // around a single struct field entity. The boolean returns true if the field
  // was found.