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<div class="book" data-level="2.2" data-chapter-title="聲明" data-filepath="ch2/ch2-02.md" data-basepath=".." data-revision="Thu Dec 31 2015 16:18:40 GMT+0800 (中国标准时间)">
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<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">
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<b>0.1.</b>
Go語言起源
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</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
</a>
</li>
<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">
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<b>0.5.</b>
致謝
</a>
</li>
</ul>
</li>
<li class="chapter " data-level="1" data-path="ch1/ch1.html">
<a href="../ch1/ch1.html">
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<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>
査找重複的行
</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動畵
</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>
獲取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>
併發獲取多個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 active" 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">
<i class="fa fa-check"></i>
<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>
複數
</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>
布爾型
</a>
</li>
<li class="chapter " data-level="3.5" data-path="ch3/ch3-05.html">
<a href="../ch3/ch3-05.html">
<i class="fa fa-check"></i>
<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>
複合數據類型
</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>
Slice
</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>
Map
</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捕獲異常
</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>
基於指針對象的方法
</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>
方法值和方法表達式
</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>
接口是合約
</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: 表達式求值
</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>
基於類型斷言識别錯誤類型
</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: 併發的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: 併發的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: 併發的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的多路複用
</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: 併發的字典遍歷
</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>
併發的退出
</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>
基於共享變量的併發
</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>
內存同步
</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: 併發的非阻塞緩存
</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和線程
</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>
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<li class="chapter " 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">
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<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>
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<li class="chapter " data-level="11.3" data-path="ch11/ch11-03.html">
<a href="../ch11/ch11-03.html">
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<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">
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<b>11.6.</b>
示例函數
</a>
</li>
</ul>
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<li class="chapter " data-level="12" data-path="ch12/ch12.html">
<a href="../ch12/ch12.html">
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<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>
爲何需要反射?
</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表達式
</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表達式
</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>
獲取結構體字段標識
</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">
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<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">
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<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">
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<b>13.5.</b>
幾點忠告
</a>
</li>
</ul>
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<li class="chapter " data-level="14" data-path="CONTRIBUTORS.html">
<a href="../CONTRIBUTORS.html">
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<b>14.</b>
附録
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<h2 id="22-&#x8072;&#x660E;">2.2. &#x8072;&#x660E;</h2>
<p>&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x5B9A;&#x7FA9;&#x4E86;&#x7A0B;&#x5E8F;&#x7684;&#x5404;&#x7A2E;&#x5BE6;&#x9AD4;&#x5C0D;&#x8C61;&#x4EE5;&#x53CA;&#x90E8;&#x5206;&#x6216;&#x5168;&#x90E8;&#x7684;&#x5C6C;&#x6027;&#x3002;Go&#x8A9E;&#x8A00;&#x4E3B;&#x8981;&#x6709;&#x56DB;&#x7A2E;&#x985E;&#x578B;&#x7684;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#xFF1A;var&#x3001;const&#x3001;type&#x548C;func&#xFF0C;&#x5206;&#x522B;&#x5C0D;&#x61C9;&#x8B8A;&#x91CF;&#x3001;&#x5E38;&#x91CF;&#x3001;&#x985E;&#x578B;&#x548C;&#x51FD;&#x6578;&#x5BE6;&#x9AD4;&#x5C0D;&#x8C61;&#x7684;&#x8072;&#x660E;&#x3002;&#x9019;&#x4E00;&#x7AE0;&#x6211;&#x5011;&#x91CD;&#x9EDE;&#x8A0E;&#x8AD6;&#x8B8A;&#x91CF;&#x548C;&#x985E;&#x578B;&#x7684;&#x8072;&#x660E;&#xFF0C;&#x7B2C;&#x4E09;&#x7AE0;&#x5C07;&#x8A0E;&#x8AD6;&#x5E38;&#x91CF;&#x7684;&#x8072;&#x660E;&#xFF0C;&#x7B2C;&#x4E94;&#x7AE0;&#x5C07;&#x8A0E;&#x8AD6;&#x51FD;&#x6578;&#x7684;&#x8072;&#x660E;&#x3002;</p>
<p>&#x4E00;&#x500B;Go&#x8A9E;&#x8A00;&#x7DE8;&#x5BEB;&#x7684;&#x7A0B;&#x5E8F;&#x5C0D;&#x61C9;&#x4E00;&#x500B;&#x6216;&#x591A;&#x500B;&#x4EE5;.go&#x7232;&#x6587;&#x4EF6;&#x5F8C;&#x7DB4;&#x540D;&#x7684;&#x6E90;&#x6587;&#x4EF6;&#x4E2D;&#x3002;&#x6BCF;&#x500B;&#x6E90;&#x6587;&#x4EF6;&#x4EE5;&#x5305;&#x7684;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x958B;&#x59CB;&#xFF0C;&#x8AAC;&#x660E;&#x8A72;&#x6E90;&#x6587;&#x4EF6;&#x662F;&#x5C6C;&#x65BC;&#x54EA;&#x500B;&#x5305;&#x3002;&#x5305;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x4E4B;&#x5F8C;&#x662F;import&#x8A9E;&#x53E5;&#x5C0E;&#x5165;&#x4F9D;&#x8CF4;&#x7684;&#x5176;&#x5B83;&#x5305;&#xFF0C;&#x7136;&#x5F8C;&#x662F;&#x5305;&#x4E00;&#x7D1A;&#x7684;&#x985E;&#x578B;&#x3001;&#x8B8A;&#x91CF;&#x3001;&#x5E38;&#x91CF;&#x3001;&#x51FD;&#x6578;&#x7684;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#xFF0C;&#x5305;&#x4E00;&#x7D1A;&#x7684;&#x5404;&#x7A2E;&#x985E;&#x578B;&#x7684;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x7684;&#x9806;&#x5E8F;&#x7121;&#x95DC;&#x7DCA;&#x8981;&#xFF08;&#x8B6F;&#x8A3B;&#xFF1A;&#x51FD;&#x6578;&#x5167;&#x90E8;&#x7684;&#x540D;&#x5B57;&#x5247;&#x5FC5;&#x9B1A;&#x5148;&#x8072;&#x660E;&#x4E4B;&#x5F8C;&#x624D;&#x80FD;&#x4F7F;&#x7528;&#xFF09;&#x3002;&#x4F8B;&#x5982;&#xFF0C;&#x4E0B;&#x9762;&#x7684;&#x4F8B;&#x5B50;&#x4E2D;&#x8072;&#x660E;&#x4E86;&#x4E00;&#x500B;&#x5E38;&#x91CF;&#x3001;&#x4E00;&#x500B;&#x51FD;&#x6578;&#x548C;&#x5169;&#x500B;&#x8B8A;&#x91CF;&#xFF1A;</p>
<pre><code class="lang-Go">gopl.io/ch2/boiling
<span class="hljs-comment">// Boiling prints the boiling point of water.</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-keyword">const</span> boilingF = <span class="hljs-number">212.0</span>
<span class="hljs-keyword">func</span> main() {
<span class="hljs-keyword">var</span> f = boilingF
<span class="hljs-keyword">var</span> c = (f - <span class="hljs-number">32</span>) * <span class="hljs-number">5</span> / <span class="hljs-number">9</span>
fmt.Printf(<span class="hljs-string">&quot;boiling point = %g&#xB0;F or %g&#xB0;C\n&quot;</span>, f, c)
<span class="hljs-comment">// Output:</span>
<span class="hljs-comment">// boiling point = 212&#xB0;F or 100&#xB0;C</span>
}
</code></pre>
<p>&#x5176;&#x4E2D;&#x5E38;&#x91CF;boilingF&#x662F;&#x5728;&#x5305;&#x4E00;&#x7D1A;&#x8303;&#x570D;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x8072;&#x660E;&#x7684;&#xFF0C;&#x7136;&#x5F8C;f&#x548C;c&#x5169;&#x500B;&#x8B8A;&#x91CF;&#x662F;&#x5728;main&#x51FD;&#x6578;&#x5167;&#x90E8;&#x8072;&#x660E;&#x7684;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x8072;&#x660E;&#x7684;&#x3002;&#x5728;&#x5305;&#x4E00;&#x7D1A;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x8072;&#x660E;&#x7684;&#x540D;&#x5B57;&#x53EF;&#x5728;&#x6574;&#x500B;&#x5305;&#x5C0D;&#x61C9;&#x7684;&#x6BCF;&#x500B;&#x6E90;&#x6587;&#x4EF6;&#x4E2D;&#x8A2A;&#x554F;&#xFF0C;&#x800C;&#x4E0D;&#x662F;&#x50C5;&#x50C5;&#x5728;&#x5176;&#x8072;&#x660E;&#x8A9E;&#x53E5;&#x6240;&#x5728;&#x7684;&#x6E90;&#x6587;&#x4EF6;&#x4E2D;&#x8A2A;&#x554F;&#x3002;&#x76F8;&#x6BD4;&#x4E4B;&#x4E0B;&#xFF0C;&#x5C40;&#x90E8;&#x8072;&#x660E;&#x7684;&#x540D;&#x5B57;&#x5C31;&#x96BB;&#x80FD;&#x5728;&#x51FD;&#x6578;&#x5167;&#x90E8;&#x5F88;&#x5C0F;&#x7684;&#x8303;&#x570D;&#x88AB;&#x8A2A;&#x554F;&#x3002;</p>
<p>&#x4E00;&#x500B;&#x51FD;&#x6578;&#x7684;&#x8072;&#x660E;&#x7531;&#x4E00;&#x500B;&#x51FD;&#x6578;&#x540D;&#x5B57;&#x3001;&#x53C3;&#x6578;&#x5217;&#x8868;&#xFF08;&#x7531;&#x51FD;&#x6578;&#x7684;&#x8ABF;&#x7528;&#x8005;&#x63D0;&#x4F9B;&#x53C3;&#x6578;&#x8B8A;&#x91CF;&#x7684;&#x5177;&#x9AD4;&#x503C;&#xFF09;&#x3001;&#x4E00;&#x500B;&#x53EF;&#x9078;&#x7684;&#x8FD4;&#x8FF4;&#x503C;&#x5217;&#x8868;&#x548C;&#x5305;&#x542B;&#x51FD;&#x6578;&#x5B9A;&#x7FA9;&#x7684;&#x51FD;&#x6578;&#x9AD4;&#x7D44;&#x6210;&#x3002;&#x5982;&#x679C;&#x51FD;&#x6578;&#x6C92;&#x6709;&#x8FD4;&#x8FF4;&#x503C;&#xFF0C;&#x90A3;&#x9EBD;&#x8FD4;&#x8FF4;&#x503C;&#x5217;&#x8868;&#x662F;&#x7701;&#x7565;&#x7684;&#x3002;&#x57F7;&#x884C;&#x51FD;&#x6578;&#x5F9E;&#x51FD;&#x6578;&#x7684;&#x7B2C;&#x4E00;&#x500B;&#x8A9E;&#x53E5;&#x958B;&#x59CB;&#xFF0C;&#x4F9D;&#x6B21;&#x9806;&#x5E8F;&#x57F7;&#x884C;&#x76F4;&#x5230;&#x9047;&#x5230;renturn&#x8FD4;&#x8FF4;&#x8A9E;&#x53E5;&#xFF0C;&#x5982;&#x679C;&#x6C92;&#x6709;&#x8FD4;&#x8FF4;&#x8A9E;&#x53E5;&#x5247;&#x662F;&#x57F7;&#x884C;&#x5230;&#x51FD;&#x6578;&#x672B;&#x5C3E;&#xFF0C;&#x7136;&#x5F8C;&#x8FD4;&#x8FF4;&#x5230;&#x51FD;&#x6578;&#x8ABF;&#x7528;&#x8005;&#x3002;</p>
<p>&#x6211;&#x5011;&#x5DF2;&#x7D93;&#x770B;&#x5230;&#x904E;&#x5F88;&#x591A;&#x51FD;&#x6578;&#x8072;&#x660E;&#x548C;&#x51FD;&#x6578;&#x8ABF;&#x7528;&#x7684;&#x4F8B;&#x5B50;&#x4E86;&#xFF0C;&#x5728;&#x7B2C;&#x4E94;&#x7AE0;&#x5C07;&#x6DF1;&#x5165;&#x8A0E;&#x8AD6;&#x51FD;&#x6578;&#x7684;&#x76F8;&#x95DC;&#x7D30;&#x7BC0;&#xFF0C;&#x9019;&#x91CC;&#x96BB;&#x7C21;&#x55AE;&#x89E3;&#x91CB;&#x4E0B;&#x3002;&#x4E0B;&#x9762;&#x7684;fToC&#x51FD;&#x6578;&#x5C01;&#x88DD;&#x4E86;&#x6EAB;&#x5EA6;&#x8F49;&#x63DB;&#x7684;&#x8655;&#x7406;&#x908F;&#x8F2F;&#xFF0C;&#x9019;&#x6A23;&#x5B83;&#x96BB;&#x9700;&#x8981;&#x88AB;&#x5B9A;&#x7FA9;&#x4E00;&#x6B21;&#xFF0C;&#x5C31;&#x53EF;&#x4EE5;&#x5728;&#x591A;&#x500B;&#x5730;&#x65B9;&#x591A;&#x6B21;&#x88AB;&#x4F7F;&#x7528;&#x3002;&#x5728;&#x9019;&#x500B;&#x4F8B;&#x5B50;&#x4E2D;&#xFF0C;main&#x51FD;&#x6578;&#x5C31;&#x8ABF;&#x7528;&#x4E86;&#x5169;&#x6B21;fToC&#x51FD;&#x6578;&#xFF0C;&#x5206;&#x522B;&#x662F;&#x4F7F;&#x7528;&#x5728;&#x5C40;&#x90E8;&#x5B9A;&#x7FA9;&#x7684;&#x5169;&#x500B;&#x5E38;&#x91CF;&#x4F5C;&#x7232;&#x8ABF;&#x7528;&#x51FD;&#x6578;&#x7684;&#x53C3;&#x6578;&#x3002;</p>
<pre><code class="lang-Go">gopl.io/ch2/ftoc
<span class="hljs-comment">// Ftoc prints two Fahrenheit-to-Celsius conversions.</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-keyword">func</span> main() {
<span class="hljs-keyword">const</span> freezingF, boilingF = <span class="hljs-number">32.0</span>, <span class="hljs-number">212.0</span>
fmt.Printf(<span class="hljs-string">&quot;%g&#xB0;F = %g&#xB0;C\n&quot;</span>, freezingF, fToC(freezingF)) <span class="hljs-comment">// &quot;32&#xB0;F = 0&#xB0;C&quot;</span>
fmt.Printf(<span class="hljs-string">&quot;%g&#xB0;F = %g&#xB0;C\n&quot;</span>, boilingF, fToC(boilingF)) <span class="hljs-comment">// &quot;212&#xB0;F = 100&#xB0;C&quot;</span>
}
<span class="hljs-keyword">func</span> fToC(f <span class="hljs-typename">float64</span>) <span class="hljs-typename">float64</span> {
<span class="hljs-keyword">return</span> (f - <span class="hljs-number">32</span>) * <span class="hljs-number">5</span> / <span class="hljs-number">9</span>
}
</code></pre>
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