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<h3><span lang=EN-US>13. </span><span style='font-family:宋体;mso-ascii-font-family:
Arial;mso-hansi-font-family:Arial'>确保资源为对象所占有。使用显式的</span><span lang=EN-US>RAII</span><span
style='font-family:宋体;mso-ascii-font-family:Arial;mso-hansi-font-family:Arial'>和智能指针。（</span><span
lang=EN-US>Ensure resources are owned by objects. Use explicit RAII and smart
pointers.</span><span style='font-family:宋体;mso-ascii-font-family:Arial;
mso-hansi-font-family:Arial'>）</span></h3>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><b style='mso-bidi-font-weight:normal'><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>摘要</span></b></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"'>如果有强力的工具，那么就不要手工去做：</span><span
lang=EN-US>C++</span><span style='font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"'>的“资源获取暨初始化”（</span><span lang=EN-US>"resource
acquisition is initialization", RAII</span><span style='font-family:宋体;
mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>）惯用法就是正确处理资源的<i
style='mso-bidi-font-style:normal'>那个</i>强力工具。</span><span lang=EN-US>RAII</span><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>使得编译器可以提供自动而强有力的保证，在其它语言中，程序员需要为类似惯用法手动编写代码，而这是很脆弱的。在分配一个原始资源时，要立即把它传给占有它的对象。绝对不要在一条语句中分配一个以上的资源。</span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><b style='mso-bidi-font-weight:normal'><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>讨论</span></b></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span lang=EN-US>C++</span><span style='font-family:宋体;
mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:"Times New Roman"'>在语言层面强制的构造</span><span
lang=EN-US>/</span><span style='font-family:宋体;mso-ascii-font-family:"Times New Roman";
mso-hansi-font-family:"Times New Roman"'>析构恰好与资源获取</span><span lang=EN-US>/</span><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>释放这对函数相对应，如</span><span class=SpellE><b style='mso-bidi-font-weight:
normal'><span lang=EN-US>fopen</span></b></span><span lang=EN-US> / <span
class=SpellE><b style='mso-bidi-font-weight:normal'>fclose</b></span></span><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>，</span><b style='mso-bidi-font-weight:normal'><span
lang=EN-US>lock</span></b><span lang=EN-US> / <b style='mso-bidi-font-weight:
normal'>unlock</b></span><span style='font-family:宋体;mso-ascii-font-family:
"Times New Roman";mso-hansi-font-family:"Times New Roman"'>，以及</span><b
style='mso-bidi-font-weight:normal'><span lang=EN-US>new</span></b><span
lang=EN-US> / <b style='mso-bidi-font-weight:normal'>delete</b></span><span
style='font-family:宋体;mso-ascii-font-family:"Times New Roman";mso-hansi-font-family:
"Times New Roman"'>。这使得对于自动资源管理和清理来说，基于栈（或使用引用计数）的对象成为了极桂的工具，因为对象可以在构造函数中获取资源并在析构函数中释放资源。</span></p>
<p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-family:宋体;mso-ascii-font-family:"Times New Roman";
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