[日常] Go语言圣经-函数多返回值习题

package main

import (
        "fmt"
        "golang.org/x/net/html"
        "net/http"
        "os"
        "strings"
)
/*
练习 5.5： 实现countWordsAndImages。（参考练习4.9如何分词）
*/
func main() {
        words, images, _ := CountWordsAndImages(os.Args[1])
        fmt.Printf("文字：%d,图片：%d \n",words,images)
}

// CountWordsAndImages does an HTTP GET request for the HTML
// document url and returns the number of words and images in it.
func CountWordsAndImages(url string) (words, images int, err error) {
        resp, err := http.Get(url)
        if err != nil {
                return
        }   
        doc, err := html.Parse(resp.Body)
        resp.Body.Close()
        if err != nil {
                err = fmt.Errorf("parsing HTML: %s", err)
                return
        }   
        words, images = countWordsAndImages(doc)
        //bare return
        return
}
func countWordsAndImages(n *html.Node) (words, images int) {

        texts, images := visit3(nil,0, n)
        for _, v := range texts {
                v = strings.Trim(strings.TrimSpace(v), "\r\n")
                if v == "" {
                        continue
                }   
                words += strings.Count(v, "") 
        }   
        //bare return
        return
}
//递归循环html
func visit3(texts []string, imgs int, n *html.Node) ([]string, int) {
        //文本
        if n.Type == html.TextNode {
                texts = append(texts, n.Data)
        }   
        //图片
        if n.Type == html.ElementNode && (n.Data == "img") {
                imgs++
        }
        for c := n.FirstChild; c != nil; c = c.NextSibling {
                if c.Data == "script" || c.Data == "style" {
                        continue
                }

                texts,imgs = visit3(texts, imgs, c)
        }
        //多返回值
        return texts, imgs
}