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<title>示例: 解碼S表達式 | Go语言圣经</title>
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<div class="book"
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前言
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<b>0.1.</b>
Go語言起源
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<b>0.2.</b>
Go語言項目
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<b>0.3.</b>
本書的組織
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<b>0.4.</b>
更多的信息
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<b>0.5.</b>
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致謝
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<b>1.</b>
入門
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<b>1.1.</b>
Hello, World
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<b>1.2.</b>
命令行參數
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<b>1.3.</b>
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査找重複的行
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<b>1.4.</b>
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GIF動畵
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<li class="chapter " data-level="1.5" data-path="ch1/ch1-05.html">
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<b>1.5.</b>
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獲取URL
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<b>1.6.</b>
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併發獲取多個URL
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<b>1.7.</b>
Web服務
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<b>1.8.</b>
本章要點
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<b>2.</b>
程序結構
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<b>2.1.</b>
命名
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<b>2.2.</b>
聲明
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<b>2.3.</b>
變量
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<b>2.4.</b>
賦值
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<b>2.5.</b>
類型
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<b>2.6.</b>
包和文件
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<b>2.7.</b>
作用域
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<b>3.</b>
基礎數據類型
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<b>3.1.</b>
整型
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<b>3.2.</b>
浮點數
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<b>3.3.</b>
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複數
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<b>3.4.</b>
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布爾型
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</a>
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<b>3.5.</b>
字符串
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<b>3.6.</b>
常量
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</ul>
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<b>4.</b>
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複合數據類型
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</a>
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<li class="chapter " data-level="4.1" data-path="ch4/ch4-01.html">
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<b>4.1.</b>
數組
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<li class="chapter " data-level="4.2" data-path="ch4/ch4-02.html">
<a href="../ch4/ch4-02.html">
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<b>4.2.</b>
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Slice
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</a>
</li>
<li class="chapter " data-level="4.3" data-path="ch4/ch4-03.html">
<a href="../ch4/ch4-03.html">
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<b>4.3.</b>
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Map
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</a>
</li>
<li class="chapter " data-level="4.4" data-path="ch4/ch4-04.html">
<a href="../ch4/ch4-04.html">
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<b>4.4.</b>
結構體
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</li>
<li class="chapter " data-level="4.5" data-path="ch4/ch4-05.html">
<a href="../ch4/ch4-05.html">
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<b>4.5.</b>
JSON
</a>
</li>
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<a href="../ch4/ch4-06.html">
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<b>4.6.</b>
文本和HTML模闆
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</ul>
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<b>5.</b>
函數
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<b>5.1.</b>
函數聲明
</a>
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<li class="chapter " data-level="5.2" data-path="ch5/ch5-02.html">
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<b>5.2.</b>
遞歸
</a>
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<a href="../ch5/ch5-03.html">
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<b>5.3.</b>
多返迴值
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<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">
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<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">
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<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">
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<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">
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<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">
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<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">
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<b>5.10.</b>
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Recover捕獲異常
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</a>
</li>
</ul>
</li>
<li class="chapter " data-level="6" data-path="ch6/ch6.html">
<a href="../ch6/ch6.html">
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<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">
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<b>6.2.</b>
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基於指針對象的方法
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</a>
</li>
<li class="chapter " data-level="6.3" data-path="ch6/ch6-03.html">
<a href="../ch6/ch6-03.html">
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<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">
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<b>6.4.</b>
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方法值和方法表達式
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</a>
</li>
<li class="chapter " data-level="6.5" data-path="ch6/ch6-05.html">
<a href="../ch6/ch6-05.html">
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<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">
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<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">
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<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>
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接口是合約
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</a>
</li>
<li class="chapter " data-level="7.2" data-path="ch7/ch7-02.html">
<a href="../ch7/ch7-02.html">
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<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">
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<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">
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<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>
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示例: 表達式求值
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</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>
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基於類型斷言識别錯誤類型
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</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">
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<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">
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<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">
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<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>
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示例: 併發的Clock服務
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</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>
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示例: 併發的Echo服務
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</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>
2015-12-21 04:55:18 +00:00
示例: 併發的Web爬蟲
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
基於select的多路複用
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
示例: 併發的字典遍歷
2015-12-09 07:57:17 +00:00
</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>
2015-12-28 08:08:26 +00:00
併發的退出
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
基於共享變量的併發
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
內存同步
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
示例: 併發的非阻塞緩存
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
Goroutines和線程
2015-12-09 07:57:17 +00:00
</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 " 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>
2015-12-21 04:55:18 +00:00
爲何需要反射?
2015-12-09 07:57:17 +00:00
</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>
2015-12-21 04:55:18 +00:00
示例: 編碼S表達式
2015-12-09 07:57:17 +00:00
</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 active" 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>
2015-12-21 04:55:18 +00:00
示例: 解碼S表達式
2015-12-09 07:57:17 +00:00
</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>
2015-12-28 08:08:26 +00:00
獲取結構體字段標識
2015-12-09 07:57:17 +00:00
</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>
2015-12-24 06:47:06 +00:00
<li class="chapter " data-level="14" data-path="CONTRIBUTORS.html">
2015-12-09 07:57:17 +00:00
2015-12-24 06:47:06 +00:00
<a href="../CONTRIBUTORS.html">
2015-12-09 07:57:17 +00:00
<i class="fa fa-check"></i>
2015-12-21 04:55:18 +00:00
<b>14.</b>
2015-12-09 07:57:17 +00:00
2015-12-24 06:47:06 +00:00
附録
2015-12-09 07:57:17 +00:00
</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
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<a href="../" >Go语言圣经</a>
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<h2 id="126-&#x793A;&#x4F8B;-&#x89E3;&#x78BC;s&#x8868;&#x9054;&#x5F0F;">12.6. &#x793A;&#x4F8B;: &#x89E3;&#x78BC;S&#x8868;&#x9054;&#x5F0F;</h2>
2016-01-02 08:04:45 +00:00
<p>&#x6A19;&#x6E96;&#x5EAB;&#x4E2D;encoding/...&#x4E0B;&#x6BCF;&#x500B;&#x5305;&#x4E2D;&#x63D0;&#x4F9B;&#x7684;Marshal&#x7DE8;&#x78BC;&#x51FD;&#x6578;&#x90FD;&#x6709;&#x4E00;&#x500B;&#x5C0D;&#x61C9;&#x7684;Unmarshal&#x51FD;&#x6578;&#x7528;&#x65BC;&#x89E3;&#x78BC;&#x3002;&#x4F8B;&#x5982;&#xFF0C;&#x6211;&#x5011;&#x5728;4.5&#x7BC0;&#x4E2D;&#x770B;&#x5230;&#x7684;&#xFF0C;&#x8981;&#x5C07;&#x5305;&#x542B;JSON&#x7DE8;&#x78BC;&#x683C;&#x5F0F;&#x7684;&#x5B57;&#x7BC0;slice&#x6578;&#x64DA;&#x89E3;&#x78BC;&#x7232;&#x6211;&#x5011;&#x81EA;&#x5DF1;&#x7684;Movie&#x985E;&#x578B;&#xFF08;&#xA7;12.3&#xFF09;&#xFF0C;&#x6211;&#x5011;&#x53EF;&#x4EE5;&#x9019;&#x6A23;&#x505A;&#xFF1A;</p>
<pre><code class="lang-Go">data := []<span class="hljs-typename">byte</span>{<span class="hljs-comment">/* ... */</span>}
<span class="hljs-keyword">var</span> movie Movie
err := json.Unmarshal(data, &amp;movie)
</code></pre>
<p>Unmarshal&#x51FD;&#x6578;&#x4F7F;&#x7528;&#x4E86;&#x53CD;&#x5C04;&#x6A5F;&#x88FD;&#x985E;&#x8129;&#x6539;movie&#x8B8A;&#x91CF;&#x7684;&#x6BCF;&#x500B;&#x6210;&#x54E1;&#xFF0C;&#x6839;&#x64DA;&#x8F38;&#x5165;&#x7684;&#x5167;&#x5BB9;&#x7232;Movie&#x6210;&#x54E1;&#x5275;&#x5EFA;&#x5C0D;&#x61C9;&#x7684;map&#x3001;&#x7D50;&#x69CB;&#x9AD4;&#x548C;slice&#x3002;</p>
<p>&#x73FE;&#x5728;&#x8B93;&#x6211;&#x5011;&#x7232;S&#x8868;&#x9054;&#x5F0F;&#x7DE8;&#x78BC;&#x5BE6;&#x73FE;&#x4E00;&#x500B;&#x7C21;&#x6613;&#x7684;Unmarshal&#xFF0C;&#x985E;&#x4F3C;&#x65BC;&#x524D;&#x9762;&#x7684;json.Unmarshal&#x6A19;&#x6E96;&#x5EAB;&#x51FD;&#x6578;&#xFF0C;&#x5C0D;&#x61C9;&#x6211;&#x5011;&#x4E4B;&#x524D;&#x5BE6;&#x73FE;&#x7684;sexpr.Marshal&#x51FD;&#x6578;&#x7684;&#x9006;&#x64CD;&#x4F5C;&#x3002;&#x6211;&#x5011;&#x5FC5;&#x9B1A;&#x63D0;&#x9192;&#x4E00;&#x4E0B;&#xFF0C;&#x4E00;&#x500B;&#x5065;&#x58EF;&#x7684;&#x548C;&#x901A;&#x7528;&#x7684;&#x5BE6;&#x73FE;&#x901A;&#x5E38;&#x9700;&#x8981;&#x6BD4;&#x4F8B;&#x5B50;&#x66F4;&#x591A;&#x7684;&#x4EE3;&#x78BC;&#xFF0C;&#x7232;&#x4E86;&#x4FBF;&#x65BC;&#x6F14;&#x793A;&#x6211;&#x5011;&#x91C7;&#x7528;&#x4E86;&#x7CBE;&#x7C21;&#x7684;&#x5BE6;&#x73FE;&#x3002;&#x6211;&#x5011;&#x96BB;&#x652F;&#x6301;S&#x8868;&#x9054;&#x5F0F;&#x6709;&#x9650;&#x7684;&#x5B50;&#x96C6;&#xFF0C;&#x540C;&#x6642;&#x8655;&#x7406;&#x932F;&#x8AA4;&#x7684;&#x65B9;&#x5F0F;&#x4E5F;&#x6BD4;&#x8F03;&#x7C97;&#x66B4;&#xFF0C;&#x4EE3;&#x78BC;&#x7684;&#x76EE;&#x7684;&#x662F;&#x7232;&#x4E86;&#x6F14;&#x793A;&#x53CD;&#x5C04;&#x7684;&#x7528;&#x6CD5;&#xFF0C;&#x800C;&#x4E0D;&#x662F;&#x69CB;&#x9020;&#x4E00;&#x500B;&#x5BE6;&#x7528;&#x7684;S&#x8868;&#x9054;&#x5F0F;&#x7684;&#x89E3;&#x78BC;&#x5668;&#x3002;</p>
<p>&#x8A5E;&#x6CD5;&#x5206;&#x6790;&#x5668;lexer&#x4F7F;&#x7528;&#x4E86;&#x6A19;&#x6E96;&#x5EAB;&#x4E2D;&#x7684;text/scanner&#x5305;&#x5C07;&#x8F38;&#x5165;&#x6D41;&#x7684;&#x5B57;&#x7BC0;&#x6578;&#x64DA;&#x89E3;&#x6790;&#x7232;&#x4E00;&#x500B;&#x500B;&#x985E;&#x4F3C;&#x8A3B;&#x91CB;&#x3001;&#x6A19;&#x8B58;&#x7B26;&#x3001;&#x5B57;&#x7B26;&#x4E32;&#x9762;&#x503C;&#x548C;&#x6578;&#x5B57;&#x9762;&#x503C;&#x4E4B;&#x985E;&#x7684;&#x6A19;&#x8A18;&#x3002;&#x8F38;&#x5165;&#x6383;&#x63CF;&#x5668;scanner&#x7684;Scan&#x65B9;&#x6CD5;&#x5C07;&#x63D0;&#x524D;&#x6383;&#x63CF;&#x548C;&#x8FD4;&#x8FF4;&#x4E0B;&#x4E00;&#x500B;&#x8A18;&#x865F;&#xFF0C;&#x5C0D;&#x65BC;rune&#x985E;&#x578B;&#x3002;&#x5927;&#x591A;&#x6578;&#x8A18;&#x865F;&#xFF0C;&#x6BD4;&#x5982;&#x201C;(&#x201D;&#xFF0C;&#x5C0D;&#x61C9;&#x4E00;&#x500B;&#x55AE;&#x4E00;rune&#x53EF;&#x8868;&#x793A;&#x7684;Unicode&#x5B57;&#x7B26;&#xFF0C;&#x4F46;&#x662F;text/scanner&#x4E5F;&#x53EF;&#x4EE5;&#x7528;&#x5C0F;&#x7684;&#x8CA0;&#x6578;&#x8868;&#x793A;&#x8A18;&#x865F;&#x6A19;&#x8B58;&#x7B26;&#x3001;&#x5B57;&#x7B26;&#x4E32;&#x7B49;&#x7531;&#x591A;&#x500B;&#x5B57;&#x7B26;&#x7D44;&#x6210;&#x7684;&#x8A18;&#x865F;&#x3002;&#x8ABF;&#x7528;Scan&#x65B9;&#x6CD5;&#x5C07;&#x8FD4;&#x8FF4;&#x9019;&#x4E9B;&#x8A18;&#x865F;&#x7684;&#x985E;&#x578B;&#xFF0C;&#x63A5;&#x7740;&#x8ABF;&#x7528;TokenText&#x65B9;&#x6CD5;&#x5C07;&#x8FD4;&#x8FF4;&#x8A18;&#x865F;&#x5C0D;&#x61C9;&#x7684;&#x6587;&#x672C;&#x5167;&#x5BB9;&#x3002;</p>
<p>&#x56E0;&#x7232;&#x6BCF;&#x500B;&#x89E3;&#x6790;&#x5668;&#x53EF;&#x80FD;&#x9700;&#x8981;&#x591A;&#x6B21;&#x4F7F;&#x7528;&#x7576;&#x524D;&#x7684;&#x8A18;&#x865F;&#xFF0C;&#x4F46;&#x662F;Scan&#x6703;&#x4E00;&#x76F4;&#x5411;&#x524D;&#x6383;&#x63CF;&#xFF0C;&#x6240;&#x6709;&#x6211;&#x5011;&#x5305;&#x88DD;&#x4E86;&#x4E00;&#x500B;lexer&#x6383;&#x63CF;&#x5668;&#x8F14;&#x52A9;&#x985E;&#x578B;&#xFF0C;&#x7528;&#x65BC;&#x8DDF;&#x8E64;&#x6700;&#x8FD1;&#x7531;Scan&#x65B9;&#x6CD5;&#x8FD4;&#x8FF4;&#x7684;&#x8A18;&#x865F;&#x3002;</p>
<pre><code class="lang-Go">gopl.io/ch12/sexpr
<span class="hljs-keyword">type</span> lexer <span class="hljs-keyword">struct</span> {
scan scanner.Scanner
token <span class="hljs-typename">rune</span> <span class="hljs-comment">// the current token</span>
}
<span class="hljs-keyword">func</span> (lex *lexer) next() { lex.token = lex.scan.Scan() }
<span class="hljs-keyword">func</span> (lex *lexer) text() <span class="hljs-typename">string</span> { <span class="hljs-keyword">return</span> lex.scan.TokenText() }
<span class="hljs-keyword">func</span> (lex *lexer) consume(want <span class="hljs-typename">rune</span>) {
<span class="hljs-keyword">if</span> lex.token != want { <span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> Not an example of good error handling.</span>
<span class="hljs-built_in">panic</span>(fmt.Sprintf(<span class="hljs-string">&quot;got %q, want %q&quot;</span>, lex.text(), want))
}
lex.next()
}
</code></pre>
<p>&#x73FE;&#x5728;&#x8B93;&#x6211;&#x5011;&#x8F49;&#x5230;&#x8A9E;&#x6CD5;&#x89E3;&#x6790;&#x5668;&#x3002;&#x5B83;&#x4E3B;&#x8981;&#x5305;&#x542B;&#x5169;&#x500B;&#x529F;&#x80FD;&#x3002;&#x7B2C;&#x4E00;&#x500B;&#x662F;read&#x51FD;&#x6578;&#xFF0C;&#x7528;&#x65BC;&#x8B80;&#x53D6;S&#x8868;&#x9054;&#x5F0F;&#x7684;&#x7576;&#x524D;&#x6A19;&#x8A18;&#xFF0C;&#x7136;&#x5F8C;&#x6839;&#x64DA;S&#x8868;&#x9054;&#x5F0F;&#x7684;&#x7576;&#x524D;&#x6A19;&#x8A18;&#x66F4;&#x65B0;&#x53EF;&#x53D6;&#x5730;&#x5740;&#x7684;reflect.Value&#x5C0D;&#x61C9;&#x7684;&#x8B8A;&#x91CF;v&#x3002;</p>
<pre><code class="lang-Go"><span class="hljs-keyword">func</span> read(lex *lexer, v reflect.Value) {
<span class="hljs-keyword">switch</span> lex.token {
<span class="hljs-keyword">case</span> scanner.Ident:
<span class="hljs-comment">// The only valid identifiers are</span>
<span class="hljs-comment">// &quot;nil&quot; and struct field names.</span>
<span class="hljs-keyword">if</span> lex.text() == <span class="hljs-string">&quot;nil&quot;</span> {
v.Set(reflect.Zero(v.Type()))
lex.next()
<span class="hljs-keyword">return</span>
}
<span class="hljs-keyword">case</span> scanner.String:
s, _ := strconv.Unquote(lex.text()) <span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> ignoring errors</span>
v.SetString(s)
lex.next()
<span class="hljs-keyword">return</span>
<span class="hljs-keyword">case</span> scanner.Int:
i, _ := strconv.Atoi(lex.text()) <span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> ignoring errors</span>
v.SetInt(<span class="hljs-typename">int64</span>(i))
lex.next()
<span class="hljs-keyword">return</span>
<span class="hljs-keyword">case</span> <span class="hljs-string">&apos;(&apos;</span>:
lex.next()
readList(lex, v)
lex.next() <span class="hljs-comment">// consume &apos;)&apos;</span>
<span class="hljs-keyword">return</span>
}
<span class="hljs-built_in">panic</span>(fmt.Sprintf(<span class="hljs-string">&quot;unexpected token %q&quot;</span>, lex.text()))
}
</code></pre>
<p>&#x6211;&#x5011;&#x7684;S&#x8868;&#x9054;&#x5F0F;&#x4F7F;&#x7528;&#x6A19;&#x8B58;&#x7B26;&#x5340;&#x5206;&#x5169;&#x500B;&#x4E0D;&#x540C;&#x985E;&#x578B;&#xFF0C;&#x7D50;&#x69CB;&#x9AD4;&#x6210;&#x54E1;&#x540D;&#x548C;nil&#x503C;&#x7684;&#x6307;&#x91DD;&#x3002;read&#x51FD;&#x6578;&#x503C;&#x8655;&#x7406;nil&#x985E;&#x578B;&#x7684;&#x6A19;&#x8B58;&#x7B26;&#x3002;&#x7576;&#x9047;&#x5230;scanner.Ident&#x7232;&#x201C;nil&#x201D;&#x662F;&#xFF0C;&#x4F7F;&#x7528;reflect.Zero&#x51FD;&#x6578;&#x5C07;&#x8B8A;&#x91CF;v&#x8A2D;&#x7F6E;&#x7232;&#x96F6;&#x503C;&#x3002;&#x800C;&#x5176;&#x5B83;&#x4EFB;&#x4F55;&#x985E;&#x578B;&#x7684;&#x6A19;&#x8B58;&#x7B26;&#xFF0C;&#x6211;&#x5011;&#x90FD;&#x4F5C;&#x7232;&#x932F;&#x8AA4;&#x8655;&#x7406;&#x3002;&#x5F8C;&#x9762;&#x7684;readList&#x51FD;&#x6578;&#x5C07;&#x8655;&#x7406;&#x7D50;&#x69CB;&#x9AD4;&#x7684;&#x6210;&#x54E1;&#x540D;&#x3002;</p>
<p>&#x4E00;&#x500B;&#x201C;(&#x201D;&#x6A19;&#x8A18;&#x5C0D;&#x61C9;&#x4E00;&#x500B;&#x5217;&#x8868;&#x7684;&#x958B;&#x59CB;&#x3002;&#x7B2C;&#x4E8C;&#x500B;&#x51FD;&#x6578;readList&#xFF0C;&#x5C07;&#x4E00;&#x500B;&#x5217;&#x8868;&#x89E3;&#x78BC;&#x5230;&#x4E00;&#x500B;&#x805A;&#x5408;&#x985E;&#x578B;&#x4E2D;&#xFF08;map&#x3001;&#x7D50;&#x69CB;&#x9AD4;&#x3001;slice&#x6216;&#x6578;&#x7D44;&#xFF09;&#xFF0C;&#x5177;&#x9AD4;&#x985E;&#x578B;&#x4F9D;&#x7136;&#x65BC;&#x50B3;&#x5165;&#x5F85;&#x586B;&#x5145;&#x8B8A;&#x91CF;&#x7684;&#x985E;&#x578B;&#x3002;&#x6BCF;&#x6B21;&#x9047;&#x5230;&#x9019;&#x7A2E;&#x60C5;&#x6CC1;&#xFF0C;&#x5FAA;&#x74B0;&#x7E7C;&#x7E8C;&#x89E3;&#x6790;&#x6BCF;&#x500B;&#x5143;&#x7D20;&#x76F4;&#x5230;&#x9047;&#x5230;&#x65BC;&#x958B;&#x59CB;&#x6A19;&#x8A18;&#x5339;&#x914D;&#x7684;&#x7D50;&#x675F;&#x6A19;&#x8A18;&#x201C;)&#x201D;&#xFF0C;endList&#x51FD;&#x6578;&#x7528;&#x65BC;&#x6AA2;&#x6E2C;&#x7D50;&#x675F;&#x6A19;&#x8A18;&#x3002;</p>
<p>&#x6700;&#x6709;&#x8DA3;&#x7684;&#x90E8;&#x5206;&#x662F;&#x905E;&#x6B78;&#x3002;&#x6700;&#x7C21;&#x55AE;&#x7684;&#x662F;&#x5C0D;&#x6578;&#x7D44;&#x985E;&#x578B;&#x7684;&#x8655;&#x7406;&#x3002;&#x76F4;&#x5230;&#x9047;&#x5230;&#x201C;)&#x201D;&#x7D50;&#x675F;&#x6A19;&#x8A18;&#xFF0C;&#x6211;&#x5011;&#x4F7F;&#x7528;Index&#x51FD;&#x6578;&#x4F86;&#x7372;&#x53D6;&#x6578;&#x7D44;&#x6BCF;&#x500B;&#x5143;&#x7D20;&#x7684;&#x5730;&#x5740;&#xFF0C;&#x7136;&#x5F8C;&#x905E;&#x6B78;&#x8ABF;&#x7528;read&#x51FD;&#x6578;&#x8655;&#x7406;&#x3002;&#x548C;&#x5176;&#x5B83;&#x932F;&#x8AA4;&#x985E;&#x4F3C;&#xFF0C;&#x5982;&#x679C;&#x8F38;&#x5165;&#x6578;&#x64DA;&#x5C0E;&#x81F4;&#x89E3;&#x78BC;&#x5668;&#x7684;&#x5F15;&#x7528;&#x8D85;&#x51FA;&#x4E86;&#x6578;&#x7D44;&#x7684;&#x8303;&#x570D;&#xFF0C;&#x89E3;&#x78BC;&#x5668;&#x5C07;&#x62CB;&#x51FA;panic&#x7570;&#x5E38;&#x3002;slice&#x4E5F;&#x91C7;&#x7528;&#x985E;&#x4F3C;&#x65B9;&#x6CD5;&#x89E3;&#x6790;&#xFF0C;&#x4E0D;&#x540C;&#x7684;&#x662F;&#x6211;&#x5011;&#x5C07;&#x7232;&#x6BCF;&#x500B;&#x5143;&#x7D20;&#x5275;&#x5EFA;&#x65B0;&#x7684;&#x8B8A;&#x91CF;&#xFF0C;&#x7136;&#x5F8C;&#x5C07;&#x5143;&#x7D20;&#x6DFB;&#x52A0;&#x5230;slice&#x7684;&#x672B;&#x5C3E;&#x3002;</p>
<p>&#x5728;&#x5FAA;&#x74B0;&#x8655;&#x7406;&#x7D50;&#x69CB;&#x9AD4;&#x548C;map&#x6BCF;&#x500B;&#x5143;&#x7D20;&#x6642;&#x5FC5;&#x9B1A;&#x89E3;&#x78BC;&#x4E00;&#x500B;(key value)&#x683C;&#x5F0F;&#x7684;&#x5C0D;&#x61C9;&#x5B50;&#x5217;&#x8868;&#x3002;&#x5C0D;&#x65BC;&#x7D50;&#x69CB;&#x9AD4;&#xFF0C;key&#x90E8;&#x5206;&#x5C0D;&#x65BC;&#x6210;&#x54E1;&#x7684;&#x540D;&#x5B57;&#x3002;&#x548C;&#x6578;&#x7D44;&#x985E;&#x4F3C;&#xFF0C;&#x6211;&#x5011;&#x4F7F;&#x7528;FieldByName&#x627E;&#x5230;&#x7D50;&#x69CB;&#x9AD4;&#x5C0D;&#x61C9;&#x6210;&#x54E1;&#x7684;&#x8B8A;&#x91CF;&#xFF0C;&#x7136;&#x5F8C;&#x905E;&#x6B78;&#x8ABF;&#x7528;read&#x51FD;&#x6578;&#x8655;&#x7406;&#x3002;&#x5C0D;&#x65BC;map&#xFF0C;key&#x53EF;&#x80FD;&#x662F;&#x4EFB;&#x610F;&#x985E;&#x578B;&#xFF0C;&#x5C0D;&#x5143;&#x7D20;&#x7684;&#x8655;&#x7406;&#x65B9;&#x5F0F;&#x548C;slice&#x985E;&#x4F3C;&#xFF0C;&#x6211;&#x5011;&#x5275;&#x5EFA;&#x4E00;&#x500B;&#x65B0;&#x7684;&#x8B8A;&#x91CF;&#xFF0C;&#x7136;&#x5F8C;&#x905E;&#x6B78;&#x586B;&#x5145;&#x5B83;&#xFF0C;&#x6700;&#x5F8C;&#x5C07;&#x65B0;&#x89E3;&#x6790;&#x5230;&#x7684;key/value&#x5C0D;&#x6DFB;&#x52A0;&#x5230;map&#x3002;</p>
<pre><code class="lang-Go"><span class="hljs-keyword">func</span> readList(lex *lexer, v reflect.Value) {
<span class="hljs-keyword">switch</span> v.Kind() {
<span class="hljs-keyword">case</span> reflect.Array: <span class="hljs-comment">// (item ...)</span>
<span class="hljs-keyword">for</span> i := <span class="hljs-number">0</span>; !endList(lex); i++ {
read(lex, v.Index(i))
}
<span class="hljs-keyword">case</span> reflect.Slice: <span class="hljs-comment">// (item ...)</span>
<span class="hljs-keyword">for</span> !endList(lex) {
item := reflect.New(v.Type().Elem()).Elem()
read(lex, item)
v.Set(reflect.Append(v, item))
}
<span class="hljs-keyword">case</span> reflect.Struct: <span class="hljs-comment">// ((name value) ...)</span>
<span class="hljs-keyword">for</span> !endList(lex) {
lex.consume(<span class="hljs-string">&apos;(&apos;</span>)
<span class="hljs-keyword">if</span> lex.token != scanner.Ident {
<span class="hljs-built_in">panic</span>(fmt.Sprintf(<span class="hljs-string">&quot;got token %q, want field name&quot;</span>, lex.text()))
}
name := lex.text()
lex.next()
read(lex, v.FieldByName(name))
lex.consume(<span class="hljs-string">&apos;)&apos;</span>)
}
<span class="hljs-keyword">case</span> reflect.Map: <span class="hljs-comment">// ((key value) ...)</span>
v.Set(reflect.MakeMap(v.Type()))
<span class="hljs-keyword">for</span> !endList(lex) {
lex.consume(<span class="hljs-string">&apos;(&apos;</span>)
key := reflect.New(v.Type().Key()).Elem()
read(lex, key)
value := reflect.New(v.Type().Elem()).Elem()
read(lex, value)
v.SetMapIndex(key, value)
lex.consume(<span class="hljs-string">&apos;)&apos;</span>)
}
<span class="hljs-keyword">default</span>:
<span class="hljs-built_in">panic</span>(fmt.Sprintf(<span class="hljs-string">&quot;cannot decode list into %v&quot;</span>, v.Type()))
}
}
<span class="hljs-keyword">func</span> endList(lex *lexer) <span class="hljs-typename">bool</span> {
<span class="hljs-keyword">switch</span> lex.token {
<span class="hljs-keyword">case</span> scanner.EOF:
<span class="hljs-built_in">panic</span>(<span class="hljs-string">&quot;end of file&quot;</span>)
<span class="hljs-keyword">case</span> <span class="hljs-string">&apos;)&apos;</span>:
<span class="hljs-keyword">return</span> <span class="hljs-constant">true</span>
}
<span class="hljs-keyword">return</span> <span class="hljs-constant">false</span>
}
</code></pre>
<p>&#x6700;&#x5F8C;&#xFF0C;&#x6211;&#x5011;&#x5C07;&#x89E3;&#x6790;&#x5668;&#x5305;&#x88DD;&#x7232;&#x5C0E;&#x51FA;&#x7684;Unmarshal&#x89E3;&#x78BC;&#x51FD;&#x6578;&#xFF0C;&#x96B1;&#x85CF;&#x4E86;&#x4E00;&#x4E9B;&#x521D;&#x59CB;&#x5316;&#x548C;&#x6E05;&#x7406;&#x7B49;&#x908A;&#x7DE3;&#x8655;&#x7406;&#x3002;&#x5167;&#x90E8;&#x89E3;&#x6790;&#x5668;&#x4EE5;panic&#x7684;&#x65B9;&#x5F0F;&#x62CB;&#x51FA;&#x932F;&#x8AA4;&#xFF0C;&#x4F46;&#x662F;Unmarshal&#x51FD;&#x6578;&#x901A;&#x904E;&#x5728;defer&#x8A9E;&#x53E5;&#x8ABF;&#x7528;recover&#x51FD;&#x6578;&#x4F86;&#x6355;&#x7372;&#x5167;&#x90E8;panic&#xFF08;&#xA7;5.10&#xFF09;&#xFF0C;&#x7136;&#x5F8C;&#x8FD4;&#x8FF4;&#x4E00;&#x500B;&#x5C0D;panic&#x5C0D;&#x61C9;&#x7684;&#x932F;&#x8AA4;&#x4FE1;&#x606F;&#x3002;</p>
<pre><code class="lang-Go"><span class="hljs-comment">// Unmarshal parses S-expression data and populates the variable</span>
<span class="hljs-comment">// whose address is in the non-nil pointer out.</span>
<span class="hljs-keyword">func</span> Unmarshal(data []<span class="hljs-typename">byte</span>, out <span class="hljs-keyword">interface</span>{}) (err error) {
lex := &amp;lexer{scan: scanner.Scanner{Mode: scanner.GoTokens}}
lex.scan.Init(bytes.NewReader(data))
lex.next() <span class="hljs-comment">// get the first token</span>
<span class="hljs-keyword">defer</span> <span class="hljs-keyword">func</span>() {
<span class="hljs-comment">// <span class="hljs-doctag">NOTE:</span> this is not an example of ideal error handling.</span>
<span class="hljs-keyword">if</span> x := <span class="hljs-built_in">recover</span>(); x != <span class="hljs-constant">nil</span> {
err = fmt.Errorf(<span class="hljs-string">&quot;error at %s: %v&quot;</span>, lex.scan.Position, x)
}
}()
read(lex, reflect.ValueOf(out).Elem())
<span class="hljs-keyword">return</span> <span class="hljs-constant">nil</span>
}
</code></pre>
<p>&#x751F;&#x7523;&#x5BE6;&#x73FE;&#x4E0D;&#x61C9;&#x8A72;&#x5C0D;&#x4EFB;&#x4F55;&#x8F38;&#x5165;&#x554F;&#x984C;&#x90FD;&#x7528;panic&#x5F62;&#x5F0F;&#x5831;&#x544A;&#xFF0C;&#x800C;&#x4E14;&#x61C9;&#x8A72;&#x5831;&#x544A;&#x4E00;&#x4E9B;&#x932F;&#x8AA4;&#x76F8;&#x95DC;&#x7684;&#x4FE1;&#x606F;&#xFF0C;&#x4F8B;&#x5982;&#x51FA;&#x73FE;&#x932F;&#x8AA4;&#x8F38;&#x5165;&#x7684;&#x884C;&#x865F;&#x548C;&#x4F4D;&#x7F6E;&#x7B49;&#x3002;&#x76E1;&#x7BA1;&#x5982;&#x6B64;&#xFF0C;&#x6211;&#x5011;&#x5E0C;&#x671B;&#x901A;&#x904E;&#x9019;&#x500B;&#x4F8B;&#x5B50;&#x4F86;&#x5C55;&#x793A;&#x985E;&#x4F3C;encoding/json&#x7B49;&#x5305;&#x5E95;&#x5C64;&#x4EE3;&#x78BC;&#x7684;&#x5BE6;&#x73FE;&#x601D;&#x8DEF;&#xFF0C;&#x4EE5;&#x53CA;&#x5982;&#x4F55;&#x4F7F;&#x7528;&#x53CD;&#x5C04;&#x6A5F;&#x88FD;&#x4F86;&#x586B;&#x5145;&#x6578;&#x64DA;&#x7D50;&#x69CB;&#x3002;</p>
<p><strong>&#x7DF4;&#x7FD2; 12.8&#xFF1A;</strong> sexpr.Unmarshal&#x51FD;&#x6578;&#x548C;json.Marshal&#x4E00;&#x6A23;&#xFF08;&#x8B6F;&#x8A3B;&#xFF1A;&#x9019;&#x53EF;&#x80FD;&#x662F;&#x7B46;&#x8AA4;&#xFF0C;&#x6211;&#x89BA;&#x5F97;&#x61C9;&#x8A72;&#x662F;&#x6307;<code>json.Unmarshal</code>&#x51FD;&#x6578;&#xFF09;&#xFF0C;&#x90FD;&#x8981;&#x6C42;&#x5728;&#x89E3;&#x78BC;&#x524D;&#x8F38;&#x5165;&#x5B8C;&#x6574;&#x7684;&#x5B57;&#x7BC0;slice&#x3002;&#x5B9A;&#x7FA9;&#x4E00;&#x500B;&#x548C;json.Decoder&#x985E;&#x4F3C;&#x7684;sexpr.Decoder&#x985E;&#x578B;&#xFF0C;&#x652F;&#x6301;&#x5F9E;&#x4E00;&#x500B;io.Reader&#x6D41;&#x89E3;&#x78BC;&#x3002;&#x8129;&#x6539;sexpr.Unmarshal&#x51FD;&#x6578;&#xFF0C;&#x4F7F;&#x7528;&#x9019;&#x500B;&#x65B0;&#x7684;&#x985E;&#x578B;&#x5BE6;&#x73FE;&#x3002;</p>
<p><strong>&#x7DF4;&#x7FD2; 12.9&#xFF1A;</strong> &#x7DE8;&#x5BEB;&#x4E00;&#x500B;&#x57FA;&#x65BC;&#x6A19;&#x8A18;&#x7684;API&#x7528;&#x65BC;&#x89E3;&#x78BC;S&#x8868;&#x9054;&#x5F0F;&#xFF0C;&#x53C3;&#x8003;xml.Decoder&#xFF08;7.14&#xFF09;&#x7684;&#x98A8;&#x683C;&#x3002;&#x4F60;&#x5C07;&#x9700;&#x8981;&#x4E94;&#x7A2E;&#x985E;&#x578B;&#x7684;&#x6A19;&#x8A18;&#xFF1A;Symbol&#x3001;String&#x3001;Int&#x3001;StartList&#x548C;EndList&#x3002;</p>
<p><strong>&#x7DF4;&#x7FD2; 12.10&#xFF1A;</strong> &#x64F4;&#x5C55;sexpr.Unmarshal&#x51FD;&#x6578;&#xFF0C;&#x652F;&#x6301;&#x5E03;&#x723E;&#x578B;&#x3001;&#x6D6E;&#x9EDE;&#x6578;&#x548C;interface&#x985E;&#x578B;&#x7684;&#x89E3;&#x78BC;&#xFF0C;&#x4F7F;&#x7528; <strong>&#x7DF4;&#x7FD2; 12.3&#xFF1A;</strong> &#x7684;&#x65B9;&#x6848;&#x3002;&#xFF08;&#x63D0;&#x793A;&#xFF1A;&#x8981;&#x89E3;&#x78BC;&#x63A5;&#x53E3;&#xFF0C;&#x4F60;&#x9700;&#x8981;&#x5C07;name&#x6620;&#x5C04;&#x5230;&#x6BCF;&#x500B;&#x652F;&#x6301;&#x985E;&#x578B;&#x7684;reflect.Type&#x3002;&#xFF09;</p>
2015-12-09 07:57:17 +00:00
</section>
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