package funcs import ( "code.google.com/p/go.net/html" "fmt" "regexp" ) type Displayer interface { Display(nodes []*html.Node) } type TextDisplayer struct { } func (t TextDisplayer) Display(nodes []*html.Node) { for _, node := range nodes { if node.Type == html.TextNode { fmt.Println(node.Data) } children := []*html.Node{} child := node.FirstChild for child != nil { children = append(children, child) child = child.NextSibling } t.Display(children) } } type AttrDisplayer struct { Attr string } func (a AttrDisplayer) Display(nodes []*html.Node) { for _, node := range nodes { attributes := node.Attr for _, attr := range attributes { if attr.Key == a.Attr { fmt.Println(attr.Val) } } } } var ( // Display function helpers displayMatcher *regexp.Regexp = regexp.MustCompile(`\{[^\}]*\}$`) textFuncMatcher = regexp.MustCompile(`^text\{\}$`) attrFuncMatcher = regexp.MustCompile(`^attr\{([^\}]*)\}$`) ) func NewDisplayFunc(text string) (Displayer, error) { if !displayMatcher.MatchString(text) { return nil, fmt.Errorf("Not a display function") } switch { case textFuncMatcher.MatchString(text): return TextDisplayer{}, nil case attrFuncMatcher.MatchString(text): matches := attrFuncMatcher.FindStringSubmatch(text) if len(matches) != 2 { return nil, fmt.Errorf("") } else { return AttrDisplayer{matches[1]}, nil } } return nil, fmt.Errorf("Not a display function") }