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<div class="book" data-level="10.5" data-chapter-title="匿名導入" data-filepath="ch10/ch10-05.md" data-basepath=".." data-revision="Mon Dec 14 2015 11:30:54 GMT+0800 (中国标准时间)">
2015-12-09 07:57:17 +00:00
<div class="book-summary">
<nav role="navigation">
<ul class="summary">
<li class="chapter " data-level="0" data-path="index.html">
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前言
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<ul class="articles">
<li class="chapter " data-level="0.1" data-path="ch0/ch0-01.html">
<a href="../ch0/ch0-01.html">
<i class="fa fa-check"></i>
<b>0.1.</b>
Go語言起源
</a>
</li>
<li class="chapter " data-level="0.2" data-path="ch0/ch0-02.html">
<a href="../ch0/ch0-02.html">
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<b>0.2.</b>
Go語言項目
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<li class="chapter " data-level="0.3" data-path="ch0/ch0-03.html">
<a href="../ch0/ch0-03.html">
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<b>0.3.</b>
本書的組織
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<li class="chapter " data-level="0.4" data-path="ch0/ch0-04.html">
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<b>0.4.</b>
更多的信息
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<li class="chapter " data-level="0.5" data-path="ch0/ch0-05.html">
<a href="../ch0/ch0-05.html">
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<b>0.5.</b>
緻謝
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="1" data-path="ch1/ch1.html">
<a href="../ch1/ch1.html">
<i class="fa fa-check"></i>
<b>1.</b>
入門
</a>
<ul class="articles">
<li class="chapter " data-level="1.1" data-path="ch1/ch1-01.html">
<a href="../ch1/ch1-01.html">
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<b>1.1.</b>
Hello, World
</a>
</li>
<li class="chapter " data-level="1.2" data-path="ch1/ch1-02.html">
<a href="../ch1/ch1-02.html">
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<b>1.2.</b>
命令行參數
</a>
</li>
<li class="chapter " data-level="1.3" data-path="ch1/ch1-03.html">
<a href="../ch1/ch1-03.html">
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<b>1.3.</b>
査找重復的行
</a>
</li>
<li class="chapter " data-level="1.4" data-path="ch1/ch1-04.html">
<a href="../ch1/ch1-04.html">
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<b>1.4.</b>
GIF動畫
</a>
</li>
<li class="chapter " data-level="1.5" data-path="ch1/ch1-05.html">
<a href="../ch1/ch1-05.html">
<i class="fa fa-check"></i>
<b>1.5.</b>
穫取URL
</a>
</li>
<li class="chapter " data-level="1.6" data-path="ch1/ch1-06.html">
<a href="../ch1/ch1-06.html">
<i class="fa fa-check"></i>
<b>1.6.</b>
併髮穫取多個URL
</a>
</li>
<li class="chapter " data-level="1.7" data-path="ch1/ch1-07.html">
<a href="../ch1/ch1-07.html">
<i class="fa fa-check"></i>
<b>1.7.</b>
Web服務
</a>
</li>
<li class="chapter " data-level="1.8" data-path="ch1/ch1-08.html">
<a href="../ch1/ch1-08.html">
<i class="fa fa-check"></i>
<b>1.8.</b>
本章要點
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="2" data-path="ch2/ch2.html">
<a href="../ch2/ch2.html">
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<b>2.</b>
程序結構
</a>
<ul class="articles">
<li class="chapter " data-level="2.1" data-path="ch2/ch2-01.html">
<a href="../ch2/ch2-01.html">
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<b>2.1.</b>
命名
</a>
</li>
<li class="chapter " data-level="2.2" data-path="ch2/ch2-02.html">
<a href="../ch2/ch2-02.html">
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<b>2.2.</b>
聲明
</a>
</li>
<li class="chapter " data-level="2.3" data-path="ch2/ch2-03.html">
<a href="../ch2/ch2-03.html">
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<b>2.3.</b>
變量
</a>
</li>
<li class="chapter " data-level="2.4" data-path="ch2/ch2-04.html">
<a href="../ch2/ch2-04.html">
<i class="fa fa-check"></i>
<b>2.4.</b>
賦值
</a>
</li>
<li class="chapter " data-level="2.5" data-path="ch2/ch2-05.html">
<a href="../ch2/ch2-05.html">
<i class="fa fa-check"></i>
<b>2.5.</b>
類型
</a>
</li>
<li class="chapter " data-level="2.6" data-path="ch2/ch2-06.html">
<a href="../ch2/ch2-06.html">
<i class="fa fa-check"></i>
<b>2.6.</b>
包和文件
</a>
</li>
<li class="chapter " data-level="2.7" data-path="ch2/ch2-07.html">
<a href="../ch2/ch2-07.html">
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<b>2.7.</b>
作用域
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="3" data-path="ch3/ch3.html">
<a href="../ch3/ch3.html">
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<b>3.</b>
基礎數據類型
</a>
<ul class="articles">
<li class="chapter " data-level="3.1" data-path="ch3/ch3-01.html">
<a href="../ch3/ch3-01.html">
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<b>3.1.</b>
整型
</a>
</li>
<li class="chapter " data-level="3.2" data-path="ch3/ch3-02.html">
<a href="../ch3/ch3-02.html">
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<b>3.2.</b>
浮點數
</a>
</li>
<li class="chapter " data-level="3.3" data-path="ch3/ch3-03.html">
<a href="../ch3/ch3-03.html">
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<b>3.3.</b>
復數
</a>
</li>
<li class="chapter " data-level="3.4" data-path="ch3/ch3-04.html">
<a href="../ch3/ch3-04.html">
<i class="fa fa-check"></i>
<b>3.4.</b>
佈爾型
</a>
</li>
<li class="chapter " data-level="3.5" data-path="ch3/ch3-05.html">
<a href="../ch3/ch3-05.html">
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<b>3.5.</b>
字符串
</a>
</li>
<li class="chapter " data-level="3.6" data-path="ch3/ch3-06.html">
<a href="../ch3/ch3-06.html">
<i class="fa fa-check"></i>
<b>3.6.</b>
常量
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="4" data-path="ch4/ch4.html">
<a href="../ch4/ch4.html">
<i class="fa fa-check"></i>
<b>4.</b>
復閤數據類型
</a>
<ul class="articles">
<li class="chapter " data-level="4.1" data-path="ch4/ch4-01.html">
<a href="../ch4/ch4-01.html">
<i class="fa fa-check"></i>
<b>4.1.</b>
數組
</a>
</li>
<li class="chapter " data-level="4.2" data-path="ch4/ch4-02.html">
<a href="../ch4/ch4-02.html">
<i class="fa fa-check"></i>
<b>4.2.</b>
切片
</a>
</li>
<li class="chapter " data-level="4.3" data-path="ch4/ch4-03.html">
<a href="../ch4/ch4-03.html">
<i class="fa fa-check"></i>
<b>4.3.</b>
字典
</a>
</li>
<li class="chapter " data-level="4.4" data-path="ch4/ch4-04.html">
<a href="../ch4/ch4-04.html">
<i class="fa fa-check"></i>
<b>4.4.</b>
結構體
</a>
</li>
<li class="chapter " data-level="4.5" data-path="ch4/ch4-05.html">
<a href="../ch4/ch4-05.html">
<i class="fa fa-check"></i>
<b>4.5.</b>
JSON
</a>
</li>
<li class="chapter " data-level="4.6" data-path="ch4/ch4-06.html">
<a href="../ch4/ch4-06.html">
<i class="fa fa-check"></i>
<b>4.6.</b>
文本和HTML模闆
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="5" data-path="ch5/ch5.html">
<a href="../ch5/ch5.html">
<i class="fa fa-check"></i>
<b>5.</b>
函數
</a>
<ul class="articles">
<li class="chapter " data-level="5.1" data-path="ch5/ch5-01.html">
<a href="../ch5/ch5-01.html">
<i class="fa fa-check"></i>
<b>5.1.</b>
函數聲明
</a>
</li>
<li class="chapter " data-level="5.2" data-path="ch5/ch5-02.html">
<a href="../ch5/ch5-02.html">
<i class="fa fa-check"></i>
<b>5.2.</b>
遞歸
</a>
</li>
<li class="chapter " data-level="5.3" data-path="ch5/ch5-03.html">
<a href="../ch5/ch5-03.html">
<i class="fa fa-check"></i>
<b>5.3.</b>
多返迴值
</a>
</li>
<li class="chapter " data-level="5.4" data-path="ch5/ch5-04.html">
<a href="../ch5/ch5-04.html">
<i class="fa fa-check"></i>
<b>5.4.</b>
錯誤
</a>
</li>
<li class="chapter " data-level="5.5" data-path="ch5/ch5-05.html">
<a href="../ch5/ch5-05.html">
<i class="fa fa-check"></i>
<b>5.5.</b>
函數值
</a>
</li>
<li class="chapter " data-level="5.6" data-path="ch5/ch5-06.html">
<a href="../ch5/ch5-06.html">
<i class="fa fa-check"></i>
<b>5.6.</b>
匿名函數
</a>
</li>
<li class="chapter " data-level="5.7" data-path="ch5/ch5-07.html">
<a href="../ch5/ch5-07.html">
<i class="fa fa-check"></i>
<b>5.7.</b>
可變參數
</a>
</li>
<li class="chapter " data-level="5.8" data-path="ch5/ch5-08.html">
<a href="../ch5/ch5-08.html">
<i class="fa fa-check"></i>
<b>5.8.</b>
Deferred函數
</a>
</li>
<li class="chapter " data-level="5.9" data-path="ch5/ch5-09.html">
<a href="../ch5/ch5-09.html">
<i class="fa fa-check"></i>
<b>5.9.</b>
Panic異常
</a>
</li>
<li class="chapter " data-level="5.10" data-path="ch5/ch5-10.html">
<a href="../ch5/ch5-10.html">
<i class="fa fa-check"></i>
<b>5.10.</b>
Recover捕穫異常
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="6" data-path="ch6/ch6.html">
<a href="../ch6/ch6.html">
<i class="fa fa-check"></i>
<b>6.</b>
方法
</a>
<ul class="articles">
<li class="chapter " data-level="6.1" data-path="ch6/ch6-01.html">
<a href="../ch6/ch6-01.html">
<i class="fa fa-check"></i>
<b>6.1.</b>
方法聲明
</a>
</li>
<li class="chapter " data-level="6.2" data-path="ch6/ch6-02.html">
<a href="../ch6/ch6-02.html">
<i class="fa fa-check"></i>
<b>6.2.</b>
基於指鍼對象的方法
</a>
</li>
<li class="chapter " data-level="6.3" data-path="ch6/ch6-03.html">
<a href="../ch6/ch6-03.html">
<i class="fa fa-check"></i>
<b>6.3.</b>
通過嵌入結構體來擴展類型
</a>
</li>
<li class="chapter " data-level="6.4" data-path="ch6/ch6-04.html">
<a href="../ch6/ch6-04.html">
<i class="fa fa-check"></i>
<b>6.4.</b>
方法值和方法錶達式
</a>
</li>
<li class="chapter " data-level="6.5" data-path="ch6/ch6-05.html">
<a href="../ch6/ch6-05.html">
<i class="fa fa-check"></i>
<b>6.5.</b>
示例: Bit數組
</a>
</li>
<li class="chapter " data-level="6.6" data-path="ch6/ch6-06.html">
<a href="../ch6/ch6-06.html">
<i class="fa fa-check"></i>
<b>6.6.</b>
封裝
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="7" data-path="ch7/ch7.html">
<a href="../ch7/ch7.html">
<i class="fa fa-check"></i>
<b>7.</b>
接口
</a>
<ul class="articles">
<li class="chapter " data-level="7.1" data-path="ch7/ch7-01.html">
<a href="../ch7/ch7-01.html">
<i class="fa fa-check"></i>
<b>7.1.</b>
接口是閤約
</a>
</li>
<li class="chapter " data-level="7.2" data-path="ch7/ch7-02.html">
<a href="../ch7/ch7-02.html">
<i class="fa fa-check"></i>
<b>7.2.</b>
接口類型
</a>
</li>
<li class="chapter " data-level="7.3" data-path="ch7/ch7-03.html">
<a href="../ch7/ch7-03.html">
<i class="fa fa-check"></i>
<b>7.3.</b>
實現接口的條件
</a>
</li>
<li class="chapter " data-level="7.4" data-path="ch7/ch7-04.html">
<a href="../ch7/ch7-04.html">
<i class="fa fa-check"></i>
<b>7.4.</b>
flag.Value接口
</a>
</li>
<li class="chapter " data-level="7.5" data-path="ch7/ch7-05.html">
<a href="../ch7/ch7-05.html">
<i class="fa fa-check"></i>
<b>7.5.</b>
接口值
</a>
</li>
<li class="chapter " data-level="7.6" data-path="ch7/ch7-06.html">
<a href="../ch7/ch7-06.html">
<i class="fa fa-check"></i>
<b>7.6.</b>
sort.Interface接口
</a>
</li>
<li class="chapter " data-level="7.7" data-path="ch7/ch7-07.html">
<a href="../ch7/ch7-07.html">
<i class="fa fa-check"></i>
<b>7.7.</b>
http.Handler接口
</a>
</li>
<li class="chapter " data-level="7.8" data-path="ch7/ch7-08.html">
<a href="../ch7/ch7-08.html">
<i class="fa fa-check"></i>
<b>7.8.</b>
error接口
</a>
</li>
<li class="chapter " data-level="7.9" data-path="ch7/ch7-09.html">
<a href="../ch7/ch7-09.html">
<i class="fa fa-check"></i>
<b>7.9.</b>
示例: 錶達式求值
</a>
</li>
<li class="chapter " data-level="7.10" data-path="ch7/ch7-10.html">
<a href="../ch7/ch7-10.html">
<i class="fa fa-check"></i>
<b>7.10.</b>
類型斷言
</a>
</li>
<li class="chapter " data-level="7.11" data-path="ch7/ch7-11.html">
<a href="../ch7/ch7-11.html">
<i class="fa fa-check"></i>
<b>7.11.</b>
基於類型斷言識彆錯誤類型
</a>
</li>
<li class="chapter " data-level="7.12" data-path="ch7/ch7-12.html">
<a href="../ch7/ch7-12.html">
<i class="fa fa-check"></i>
<b>7.12.</b>
通過類型斷言査詢接口
</a>
</li>
<li class="chapter " data-level="7.13" data-path="ch7/ch7-13.html">
<a href="../ch7/ch7-13.html">
<i class="fa fa-check"></i>
<b>7.13.</b>
類型分支
</a>
</li>
<li class="chapter " data-level="7.14" data-path="ch7/ch7-14.html">
<a href="../ch7/ch7-14.html">
<i class="fa fa-check"></i>
<b>7.14.</b>
示例: 基於標記的XML解碼
</a>
</li>
<li class="chapter " data-level="7.15" data-path="ch7/ch7-15.html">
<a href="../ch7/ch7-15.html">
<i class="fa fa-check"></i>
<b>7.15.</b>
補充幾點
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="8" data-path="ch8/ch8.html">
<a href="../ch8/ch8.html">
<i class="fa fa-check"></i>
<b>8.</b>
Goroutines和Channels
</a>
<ul class="articles">
<li class="chapter " data-level="8.1" data-path="ch8/ch8-01.html">
<a href="../ch8/ch8-01.html">
<i class="fa fa-check"></i>
<b>8.1.</b>
Goroutines
</a>
</li>
<li class="chapter " data-level="8.2" data-path="ch8/ch8-02.html">
<a href="../ch8/ch8-02.html">
<i class="fa fa-check"></i>
<b>8.2.</b>
示例: 併髮的Clock服務
</a>
</li>
<li class="chapter " data-level="8.3" data-path="ch8/ch8-03.html">
<a href="../ch8/ch8-03.html">
<i class="fa fa-check"></i>
<b>8.3.</b>
示例: 併髮的Echo服務
</a>
</li>
<li class="chapter " data-level="8.4" data-path="ch8/ch8-04.html">
<a href="../ch8/ch8-04.html">
<i class="fa fa-check"></i>
<b>8.4.</b>
Channels
</a>
</li>
<li class="chapter " data-level="8.5" data-path="ch8/ch8-05.html">
<a href="../ch8/ch8-05.html">
<i class="fa fa-check"></i>
<b>8.5.</b>
併行的循環
</a>
</li>
<li class="chapter " data-level="8.6" data-path="ch8/ch8-06.html">
<a href="../ch8/ch8-06.html">
<i class="fa fa-check"></i>
<b>8.6.</b>
示例: 併髮的Web爬蟲
</a>
</li>
<li class="chapter " data-level="8.7" data-path="ch8/ch8-07.html">
<a href="../ch8/ch8-07.html">
<i class="fa fa-check"></i>
<b>8.7.</b>
基於select的多路復用
</a>
</li>
<li class="chapter " data-level="8.8" data-path="ch8/ch8-08.html">
<a href="../ch8/ch8-08.html">
<i class="fa fa-check"></i>
<b>8.8.</b>
示例: 併髮的字典遍歷
</a>
</li>
<li class="chapter " data-level="8.9" data-path="ch8/ch8-09.html">
<a href="../ch8/ch8-09.html">
<i class="fa fa-check"></i>
<b>8.9.</b>
併髮的退齣
</a>
</li>
<li class="chapter " data-level="8.10" data-path="ch8/ch8-10.html">
<a href="../ch8/ch8-10.html">
<i class="fa fa-check"></i>
<b>8.10.</b>
示例: 聊天服務
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="9" data-path="ch9/ch9.html">
<a href="../ch9/ch9.html">
<i class="fa fa-check"></i>
<b>9.</b>
基於共享變量的併髮
</a>
<ul class="articles">
<li class="chapter " data-level="9.1" data-path="ch9/ch9-01.html">
<a href="../ch9/ch9-01.html">
<i class="fa fa-check"></i>
<b>9.1.</b>
競爭條件
</a>
</li>
<li class="chapter " data-level="9.2" data-path="ch9/ch9-02.html">
<a href="../ch9/ch9-02.html">
<i class="fa fa-check"></i>
<b>9.2.</b>
sync.Mutex互斥鎖
</a>
</li>
<li class="chapter " data-level="9.3" data-path="ch9/ch9-03.html">
<a href="../ch9/ch9-03.html">
<i class="fa fa-check"></i>
<b>9.3.</b>
sync.RWMutex讀寫鎖
</a>
</li>
<li class="chapter " data-level="9.4" data-path="ch9/ch9-04.html">
<a href="../ch9/ch9-04.html">
<i class="fa fa-check"></i>
<b>9.4.</b>
內存衕步
</a>
</li>
<li class="chapter " data-level="9.5" data-path="ch9/ch9-05.html">
<a href="../ch9/ch9-05.html">
<i class="fa fa-check"></i>
<b>9.5.</b>
sync.Once初始化
</a>
</li>
<li class="chapter " data-level="9.6" data-path="ch9/ch9-06.html">
<a href="../ch9/ch9-06.html">
<i class="fa fa-check"></i>
<b>9.6.</b>
競爭條件檢測
</a>
</li>
<li class="chapter " data-level="9.7" data-path="ch9/ch9-07.html">
<a href="../ch9/ch9-07.html">
<i class="fa fa-check"></i>
<b>9.7.</b>
示例: 併髮的非阻塞緩存
</a>
</li>
<li class="chapter " data-level="9.8" data-path="ch9/ch9-08.html">
<a href="../ch9/ch9-08.html">
<i class="fa fa-check"></i>
<b>9.8.</b>
Goroutines和綫程
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="10" data-path="ch10/ch10.html">
<a href="../ch10/ch10.html">
<i class="fa fa-check"></i>
<b>10.</b>
包和工具
</a>
<ul class="articles">
<li class="chapter " data-level="10.1" data-path="ch10/ch10-01.html">
<a href="../ch10/ch10-01.html">
<i class="fa fa-check"></i>
<b>10.1.</b>
簡介
</a>
</li>
<li class="chapter " data-level="10.2" data-path="ch10/ch10-02.html">
<a href="../ch10/ch10-02.html">
<i class="fa fa-check"></i>
<b>10.2.</b>
導入路徑
</a>
</li>
<li class="chapter " data-level="10.3" data-path="ch10/ch10-03.html">
<a href="../ch10/ch10-03.html">
<i class="fa fa-check"></i>
<b>10.3.</b>
包聲明
</a>
</li>
<li class="chapter " data-level="10.4" data-path="ch10/ch10-04.html">
<a href="../ch10/ch10-04.html">
<i class="fa fa-check"></i>
<b>10.4.</b>
導入聲明
</a>
</li>
<li class="chapter active" data-level="10.5" data-path="ch10/ch10-05.html">
<a href="../ch10/ch10-05.html">
<i class="fa fa-check"></i>
<b>10.5.</b>
匿名導入
</a>
</li>
<li class="chapter " data-level="10.6" data-path="ch10/ch10-06.html">
<a href="../ch10/ch10-06.html">
<i class="fa fa-check"></i>
<b>10.6.</b>
包和命名
</a>
</li>
<li class="chapter " data-level="10.7" data-path="ch10/ch10-07.html">
<a href="../ch10/ch10-07.html">
<i class="fa fa-check"></i>
<b>10.7.</b>
工具
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="11" data-path="ch11/ch11.html">
<a href="../ch11/ch11.html">
<i class="fa fa-check"></i>
<b>11.</b>
測試
</a>
<ul class="articles">
<li class="chapter " data-level="11.1" data-path="ch11/ch11-01.html">
<a href="../ch11/ch11-01.html">
<i class="fa fa-check"></i>
<b>11.1.</b>
go test
</a>
</li>
<li class="chapter " data-level="11.2" data-path="ch11/ch11-02.html">
<a href="../ch11/ch11-02.html">
<i class="fa fa-check"></i>
<b>11.2.</b>
測試函數
</a>
</li>
<li class="chapter " data-level="11.3" data-path="ch11/ch11-03.html">
<a href="../ch11/ch11-03.html">
<i class="fa fa-check"></i>
<b>11.3.</b>
測試覆蓋率
</a>
</li>
<li class="chapter " data-level="11.4" data-path="ch11/ch11-04.html">
<a href="../ch11/ch11-04.html">
<i class="fa fa-check"></i>
<b>11.4.</b>
基準測試
</a>
</li>
<li class="chapter " data-level="11.5" data-path="ch11/ch11-05.html">
<a href="../ch11/ch11-05.html">
<i class="fa fa-check"></i>
<b>11.5.</b>
剖析
</a>
</li>
<li class="chapter " data-level="11.6" data-path="ch11/ch11-06.html">
<a href="../ch11/ch11-06.html">
<i class="fa fa-check"></i>
<b>11.6.</b>
示例函數
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="12" data-path="ch12/ch12.html">
<a href="../ch12/ch12.html">
<i class="fa fa-check"></i>
<b>12.</b>
反射
</a>
<ul class="articles">
<li class="chapter " data-level="12.1" data-path="ch12/ch12-01.html">
<a href="../ch12/ch12-01.html">
<i class="fa fa-check"></i>
<b>12.1.</b>
為何需要反射?
</a>
</li>
<li class="chapter " data-level="12.2" data-path="ch12/ch12-02.html">
<a href="../ch12/ch12-02.html">
<i class="fa fa-check"></i>
<b>12.2.</b>
reflect.Type和reflect.Value
</a>
</li>
<li class="chapter " data-level="12.3" data-path="ch12/ch12-03.html">
<a href="../ch12/ch12-03.html">
<i class="fa fa-check"></i>
<b>12.3.</b>
Display遞歸打印
</a>
</li>
<li class="chapter " data-level="12.4" data-path="ch12/ch12-04.html">
<a href="../ch12/ch12-04.html">
<i class="fa fa-check"></i>
<b>12.4.</b>
示例: 編碼S錶達式
</a>
</li>
<li class="chapter " data-level="12.5" data-path="ch12/ch12-05.html">
<a href="../ch12/ch12-05.html">
<i class="fa fa-check"></i>
<b>12.5.</b>
通過reflect.Value脩改值
</a>
</li>
<li class="chapter " data-level="12.6" data-path="ch12/ch12-06.html">
<a href="../ch12/ch12-06.html">
<i class="fa fa-check"></i>
<b>12.6.</b>
示例: 解碼S錶達式
</a>
</li>
<li class="chapter " data-level="12.7" data-path="ch12/ch12-07.html">
<a href="../ch12/ch12-07.html">
<i class="fa fa-check"></i>
<b>12.7.</b>
穫取結構體字段標識
</a>
</li>
<li class="chapter " data-level="12.8" data-path="ch12/ch12-08.html">
<a href="../ch12/ch12-08.html">
<i class="fa fa-check"></i>
<b>12.8.</b>
顯示一個類型的方法集
</a>
</li>
<li class="chapter " data-level="12.9" data-path="ch12/ch12-09.html">
<a href="../ch12/ch12-09.html">
<i class="fa fa-check"></i>
<b>12.9.</b>
幾點忠告
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="13" data-path="ch13/ch13.html">
<a href="../ch13/ch13.html">
<i class="fa fa-check"></i>
<b>13.</b>
底層編程
</a>
<ul class="articles">
<li class="chapter " data-level="13.1" data-path="ch13/ch13-01.html">
<a href="../ch13/ch13-01.html">
<i class="fa fa-check"></i>
<b>13.1.</b>
unsafe.Sizeof, Alignof 和 Offsetof
</a>
</li>
<li class="chapter " data-level="13.2" data-path="ch13/ch13-02.html">
<a href="../ch13/ch13-02.html">
<i class="fa fa-check"></i>
<b>13.2.</b>
unsafe.Pointer
</a>
</li>
<li class="chapter " data-level="13.3" data-path="ch13/ch13-03.html">
<a href="../ch13/ch13-03.html">
<i class="fa fa-check"></i>
<b>13.3.</b>
示例: 深度相等判斷
</a>
</li>
<li class="chapter " data-level="13.4" data-path="ch13/ch13-04.html">
<a href="../ch13/ch13-04.html">
<i class="fa fa-check"></i>
<b>13.4.</b>
通過cgo調用C代碼
</a>
</li>
<li class="chapter " data-level="13.5" data-path="ch13/ch13-05.html">
<a href="../ch13/ch13-05.html">
<i class="fa fa-check"></i>
<b>13.5.</b>
幾點忠告
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="14" data-path="exercise/ex.html">
<a href="../exercise/ex.html">
<i class="fa fa-check"></i>
<b>14.</b>
習題解答
</a>
<ul class="articles">
<li class="chapter " data-level="14.1" data-path="exercise/ex-ch1.html">
<a href="../exercise/ex-ch1.html">
<i class="fa fa-check"></i>
<b>14.1.</b>
第一章 入門
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="15" data-path="errata.html">
<a href="../errata.html">
<i class="fa fa-check"></i>
<b>15.</b>
勘誤
</a>
</li>
<li class="divider"></li>
<li>
<a href="https://www.gitbook.com" target="blank" class="gitbook-link">
本書使用 GitBook 釋出
</a>
</li>
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<h2 id="105-&#x533F;&#x540D;&#x5C0E;&#x5165;">10.5. &#x533F;&#x540D;&#x5C0E;&#x5165;</h2>
<p>&#x5982;&#x679C;&#x96BB;&#x662F;&#x5C0E;&#x5165;&#x4E00;&#x500B;&#x5305;&#x800C;&#x4F75;&#x4E0D;&#x4F7F;&#x7528;&#x5C0E;&#x5165;&#x7684;&#x5305;&#x662F;&#x4E00;&#x500B;&#x7DE8;&#x8B6F;&#x932F;&#x8AA4;. &#x4F46;&#x662F;&#x6709;&#x6642;&#x5019;&#x6211;&#x5011;&#x96BB;&#x662F;&#x60F3;&#x5229;&#x7528;&#x5C0E;&#x5165;&#x5305;&#x7522;&#x751F;&#x7684;&#x526F;&#x4F5C;&#x7528;: &#x5B83;&#x6703;&#x8A08;&#x7B97;&#x5305;&#x7D1A;&#x8B8A;&#x91CF;&#x7684;&#x521D;&#x59CB;&#x5316;&#x9336;&#x9054;&#x5F0F;&#x548C;&#x57F7;&#x884C;&#x5C0E;&#x5165;&#x5305;&#x7684; init &#x521D;&#x59CB;&#x5316;&#x51FD;&#x6578; (&#xA7;2.6.2). &#x9019;&#x6642;&#x5019;&#x6211;&#x5011;&#x9700;&#x8981;&#x6291;&#x88FD;&#x201C;&#x672A;&#x4F7F;&#x7528;&#x7684;&#x5C0E;&#x5165;&#x201D;&#x932F;&#x8AA4;&#x662F;&#x95A4;&#x7406;&#x7684;, &#x6211;&#x5011;&#x53EF;&#x4EE5;&#x7528;&#x4E0B;&#x5283;&#x7DAB; <code>_</code> &#x4F86;&#x91CD;&#x547D;&#x540D;&#x5C0E;&#x5165;&#x7684;&#x5305;. &#x50CF;&#x5F80;&#x5E38;&#x4E00;&#x6A23;, &#x4E0B;&#x5283;&#x7DAB; <code>_</code> &#x70BA;&#x7A7A;&#x767D;&#x6A19;&#x8B58;&#x7B26;, &#x4F75;&#x4E0D;&#x80FD;&#x88AB;&#x8A2A;&#x554F;.</p>
<pre><code class="lang-Go"><span class="hljs-keyword">import</span> _ <span class="hljs-string">&quot;image/png&quot;</span> <span class="hljs-comment">// register PNG decoder</span>
</code></pre>
<p>&#x9019;&#x500B;&#x88AB;&#x7A31;&#x70BA;&#x533F;&#x540D;&#x5C0E;&#x5165;. &#x5B83;&#x901A;&#x5E38;&#x662F;&#x7528;&#x4F86;&#x5BE6;&#x73FE;&#x4E00;&#x500B;&#x7DE8;&#x8B6F;&#x6642;&#x6A5F;&#x88FD;, &#x7136;&#x5F8C;&#x901A;&#x904E;&#x5728;main&#x4E3B;&#x7A0B;&#x5E8F;&#x5165;&#x53E3;&#x9078;&#x64C7;&#x6027;&#x5730;&#x5C0E;&#x5165;&#x9644;&#x52A0;&#x7684;&#x5305;. &#x9996;&#x5148;, &#x8B93;&#x6211;&#x5011;&#x770B;&#x770B;&#x5982;&#x4F55;&#x4F7F;&#x7528;&#x5B83;, &#x7136;&#x5F8C;&#x518D;&#x770B;&#x770B;&#x5B83;&#x662F;&#x5982;&#x4F55;&#x5DE5;&#x4F5C;&#x7684;:</p>
<p>&#x6A19;&#x6E96;&#x5EAB;&#x7684; image &#x5716;&#x50CF;&#x5305;&#x5C0E;&#x5165;&#x4E86;&#x4E00;&#x500B; <code>Decode</code> &#x51FD;&#x6578;, &#x7528;&#x65BC;&#x5F9E; <code>io.Reader</code> &#x63A5;&#x53E3;&#x8B80;&#x53D6;&#x6578;&#x64DA;&#x4F75;&#x89E3;&#x78BC;&#x5716;&#x50CF;, &#x5B83;&#x8ABF;&#x7528;&#x5E95;&#x5C64;&#x8A3B;&#x518A;&#x7684;&#x5716;&#x50CF;&#x89E3;&#x78BC;&#x5668;&#x5DE5;&#x4F5C;, &#x7136;&#x5F8C;&#x8FD4;&#x8FF4; image.Image &#x985E;&#x578B;&#x7684;&#x5716;&#x50CF;. &#x4F7F;&#x7528; <code>image.Decode</code> &#x5F88;&#x5BB9;&#x6613;&#x7DE8;&#x5BEB;&#x4E00;&#x500B;&#x5716;&#x50CF;&#x683C;&#x5F0F;&#x7684;&#x8F49;&#x63DB;&#x5DE5;&#x5177;, &#x8B80;&#x53D6;&#x4E00;&#x7A2E;&#x683C;&#x5F0F;&#x7684;&#x5716;&#x50CF;, &#x7136;&#x5F8C;&#x7DE8;&#x78BC;&#x70BA;&#x53E6;&#x4E00;&#x7A2E;&#x5716;&#x50CF;&#x683C;&#x5F0F;:</p>
<pre><code class="lang-Go">gopl.io/ch10/jpeg
<span class="hljs-comment">// The jpeg command reads a PNG image from the standard input</span>
<span class="hljs-comment">// and writes it as a JPEG image to the standard output.</span>
<span class="hljs-keyword">package</span> main
<span class="hljs-keyword">import</span> (
<span class="hljs-string">&quot;fmt&quot;</span>
<span class="hljs-string">&quot;image&quot;</span>
<span class="hljs-string">&quot;image/jpeg&quot;</span>
_ <span class="hljs-string">&quot;image/png&quot;</span> <span class="hljs-comment">// register PNG decoder</span>
<span class="hljs-string">&quot;io&quot;</span>
<span class="hljs-string">&quot;os&quot;</span>
)
<span class="hljs-keyword">func</span> main() {
<span class="hljs-keyword">if</span> err := toJPEG(os.Stdin, os.Stdout); err != <span class="hljs-constant">nil</span> {
fmt.Fprintf(os.Stderr, <span class="hljs-string">&quot;jpeg: %v\n&quot;</span>, err)
os.Exit(<span class="hljs-number">1</span>)
}
}
<span class="hljs-keyword">func</span> toJPEG(in io.Reader, out io.Writer) error {
img, kind, err := image.Decode(in)
<span class="hljs-keyword">if</span> err != <span class="hljs-constant">nil</span> {
<span class="hljs-keyword">return</span> err
}
fmt.Fprintln(os.Stderr, <span class="hljs-string">&quot;Input format =&quot;</span>, kind)
<span class="hljs-keyword">return</span> jpeg.Encode(out, img, &amp;jpeg.Options{Quality: <span class="hljs-number">95</span>})
}
</code></pre>
<p>&#x5982;&#x679C;&#x6211;&#x5011;&#x5C07; <code>gopl.io/ch3/mandelbrot</code> (&#xA7;3.3) &#x7684;&#x8F38;&#x9F63;&#x5C0E;&#x5165;&#x5230;&#x9019;&#x500B;&#x5DE5;&#x5177;&#x7684;&#x8F38;&#x5165;, &#x5B83;&#x5C07;&#x89E3;&#x78BC;&#x8F38;&#x5165;&#x7684;PNG&#x683C;&#x5F0F;&#x5716;&#x50CF;, &#x7136;&#x5F8C;&#x8F49;&#x63DB;&#x70BA;JPEG&#x683C;&#x5F0F;&#x7684;&#x5716;&#x50CF;(&#x5716;3.3).</p>
<pre><code>$ go build gopl.io/ch3/mandelbrot
$ go build gopl.io/ch10/jpeg
$ ./mandelbrot | ./jpeg &gt;mandelbrot.jpg
Input format = png
</code></pre><p>&#x8981;&#x8A3B;&#x610F; image/png &#x5305;&#x7684;&#x533F;&#x540D;&#x5C0E;&#x5165;&#x8A9E;&#x53E5;. &#x5982;&#x679C;&#x6C92;&#x6709;&#x9019;&#x4E00;&#x884C;&#x8A9E;&#x53E5;, &#x4F9D;&#x7136;&#x53EF;&#x4EE5;&#x7DE8;&#x8B6F;&#x548C;&#x904B;&#x884C;, &#x4F46;&#x662F;&#x5B83;&#x5C07;&#x4E0D;&#x80FD;&#x8B58;&#x5F46; PNG &#x683C;&#x5F0F;&#x7684;&#x5716;&#x50CF;:</p>
<pre><code>$ go build gopl.io/ch10/jpeg
$ ./mandelbrot | ./jpeg &gt;mandelbrot.jpg
jpeg: image: unknown format
</code></pre><p>&#x4E0B;&#x9EAB;&#x7684;&#x4EE3;&#x78BC;&#x6F14;&#x793A;&#x4E86;&#x5B83;&#x7684;&#x5DE5;&#x4F5C;&#x6A5F;&#x88FD;. &#x6A19;&#x6E96;&#x5EAB;&#x63D0;&#x4F9B;&#x4E86;GIF, PNG, &#x548C; JPEG &#x683C;&#x5F0F;&#x5716;&#x50CF;&#x7684;&#x89E3;&#x78BC;&#x5668;, &#x7528;&#x6236;&#x4E5F;&#x53EF;&#x4EE5;&#x63D0;&#x4F9B;&#x81EA;&#x5DF1;&#x7684;&#x89E3;&#x78BC;&#x5668;, &#x4F46;&#x662F;&#x70BA;&#x4E86;&#x4FDD;&#x5B58;&#x7A0B;&#x5E8F;&#x9AD4;&#x7A4D;&#x8F03;&#x5C0F;, &#x5F88;&#x591A;&#x89E3;&#x78BC;&#x5668;&#x4F75;&#x6C92;&#x6709;&#x88AB;&#x5305;&#x542B;&#x76E1;&#x91CF;, &#x9664;&#x975E;&#x662F;&#x660E;&#x78BA;&#x9700;&#x8981;&#x652F;&#x6301;&#x7684;&#x683C;&#x5F0F;. image.Decode &#x51FD;&#x6578;&#x6703;&#x67FB;&#x8A62;&#x652F;&#x6301;&#x7684;&#x683C;&#x5F0F;&#x5217;&#x9336;. &#x5217;&#x9336;&#x7684;&#x6BCF;&#x500B;&#x5165;&#x53E3;&#x6307;&#x5B9A;&#x4E86;&#x56DB;&#x4EF6;&#x4E8B;&#x60C5;: &#x683C;&#x5F0F;&#x7684;&#x540D;&#x7A31;; &#x4E00;&#x500B;&#x7528;&#x65BC;&#x63CF;&#x8FF0;&#x9019;&#x7A2E;&#x5716;&#x50CF;&#x6578;&#x64DA;&#x958B;&#x982D;&#x90E8;&#x5206;&#x6A21;&#x5F0F;&#x7684;&#x5B57;&#x7B26;&#x4E32;, &#x7528;&#x65BC;&#x89E3;&#x78BC;&#x5668;&#x6AA2;&#x6E2C;&#x8B58;&#x5F46;; &#x4E00;&#x500B; Decode &#x51FD;&#x6578; &#x7528;&#x65BC;&#x89E3;&#x78BC;&#x5716;&#x50CF;; &#x4E00;&#x500B; DecodeConfig &#x51FD;&#x6578;&#x7528;&#x65BC;&#x89E3;&#x78BC;&#x5716;&#x50CF;&#x7684;&#x5927;&#x5C0F;&#x548C;&#x9854;&#x8272;&#x7A7A;&#x9593;&#x7684;&#x4FE1;&#x606F;. &#x6BCF;&#x500B;&#x5165;&#x53E3;&#x662F;&#x901A;&#x904E;&#x8ABF;&#x7528; image.RegisterFormat &#x51FD;&#x6578;&#x8A3B;&#x518A;, &#x4E00;&#x822C;&#x662F;&#x5728;&#x6BCF;&#x500B;&#x683C;&#x5F0F;&#x5305;&#x7684;&#x521D;&#x59CB;&#x5316;&#x51FD;&#x6578;&#x4E2D;&#x8ABF;&#x7528;, &#x4F8B;&#x5982; image/png &#x5305;&#x662F;&#x9019;&#x6A23;&#x7684;:</p>
<pre><code class="lang-Go"><span class="hljs-keyword">package</span> png <span class="hljs-comment">// image/png</span>
<span class="hljs-keyword">func</span> Decode(r io.Reader) (image.Image, error)
<span class="hljs-keyword">func</span> DecodeConfig(r io.Reader) (image.Config, error)
<span class="hljs-keyword">func</span> init() {
<span class="hljs-keyword">const</span> pngHeader = <span class="hljs-string">&quot;\x89PNG\r\n\x1a\n&quot;</span>
image.RegisterFormat(<span class="hljs-string">&quot;png&quot;</span>, pngHeader, Decode, DecodeConfig)
}
</code></pre>
<p>&#x6700;&#x7D42;&#x7684;&#x6548;&#x679C;&#x662F;, &#x4E3B;&#x7A0B;&#x5E8F;&#x503C;&#x9700;&#x8981;&#x533F;&#x540D;&#x5C0E;&#x5165;&#x9700;&#x8981; image.Decode &#x652F;&#x6301;&#x7684;&#x683C;&#x5F0F;&#x5C0D;&#x61C9;&#x89E3;&#x78BC;&#x5305;&#x5C31;&#x53EF;&#x4EE5;&#x89E3;&#x78BC;&#x5716;&#x50CF;&#x4E86;.</p>
<p>&#x6578;&#x64DA;&#x5EAB;&#x5305; database/sql &#x4E5F;&#x662F;&#x63A1;&#x7528;&#x4E86;&#x985E;&#x4F3C;&#x7684;&#x6280;&#x672E;, &#x8B93;&#x7528;&#x6236;&#x53EF;&#x4EE5;&#x6839;&#x64DA;&#x81EA;&#x5DF1;&#x9700;&#x8981;&#x9078;&#x64C7;&#x5C0E;&#x5165;&#x5FC5;&#x8981;&#x7684;&#x6578;&#x64DA;&#x5EAB;&#x9A45;&#x52D5;. &#x4F8B;&#x5982;:</p>
<pre><code class="lang-Go"><span class="hljs-keyword">import</span> (
<span class="hljs-string">&quot;database/mysql&quot;</span>
_ <span class="hljs-string">&quot;github.com/lib/pq&quot;</span> <span class="hljs-comment">// enable support for Postgres</span>
_ <span class="hljs-string">&quot;github.com/go-sql-driver/mysql&quot;</span> <span class="hljs-comment">// enable support for MySQL</span>
)
db, err = sql.Open(<span class="hljs-string">&quot;postgres&quot;</span>, dbname) <span class="hljs-comment">// OK</span>
db, err = sql.Open(<span class="hljs-string">&quot;mysql&quot;</span>, dbname) <span class="hljs-comment">// OK</span>
db, err = sql.Open(<span class="hljs-string">&quot;sqlite3&quot;</span>, dbname) <span class="hljs-comment">// returns error: unknown driver &quot;sqlite3&quot;</span>
</code></pre>
<p><strong>&#x7DF4;&#x7FD2; 10.1:</strong> &#x64F4;&#x5C55; jpeg &#x7A0B;&#x5E8F;, &#x652F;&#x6301;&#x4EFB;&#x610F;&#x5716;&#x50CF;&#x683C;&#x5F0F;&#x4E4B;&#x9593;&#x7684;&#x76F8;&#x4E92;&#x8F49;&#x63DB;, &#x4F7F;&#x7528; image.Decode &#x6AA2;&#x6E2C;&#x652F;&#x6301;&#x7684;&#x683C;&#x5F0F;&#x985E;&#x578B;, &#x7136;&#x5F8C;&#x8855;&#x6B65; flag &#x547D;&#x4EE4;&#x884C;&#x6A19;&#x8A8C;&#x53C3;&#x6578;&#x9078;&#x64C7;&#x8F38;&#x9F63;&#x7684;&#x683C;&#x5F0F;.</p>
<p><strong>&#x7DF4;&#x7FD2; 10.2:</strong> &#x8A2D;&#x8A08;&#x4E00;&#x500B;&#x901A;&#x7528;&#x7684;&#x58D3;&#x7E2E;&#x6587;&#x4EF6;&#x8B80;&#x53D6;&#x6846;&#x67B6;, &#x7528;&#x4F86;&#x8B80;&#x53D6; ZIP(archive/zip) &#x548C; POSIX tar(archive/tar) &#x683C;&#x5F0F;&#x58D3;&#x7E2E;&#x7684;&#x6587;&#x6A94;. &#x4F7F;&#x7528;&#x985E;&#x4F3C;&#x4E0A;&#x9EAB;&#x7684;&#x8A3B;&#x518A;&#x6A5F;&#x88FD;&#x4F86;&#x64F4;&#x5C55;&#x652F;&#x6301;&#x4E0D;&#x8855;&#x7684;&#x58D3;&#x7E2E;&#x683C;&#x5F0F;, &#x7136;&#x5F8C;&#x6839;&#x64DA;&#x9700;&#x8981;&#x901A;&#x904E;&#x533F;&#x540D;&#x5C0E;&#x5165;&#x9078;&#x64C7;&#x652F;&#x6301;&#x7684;&#x683C;&#x5F0F;.</p>
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