ES.1: Prefer the standard library to other libraries and to "handcrafted code"
ES.1: 標準庫好於其他庫和手寫代碼
Reason（原因）
Code using a library can be much easier to write than code working directly with language features, much shorter, tend to be of a higher level of abstraction, and the library code is presumably already tested. The ISO C++ Standard Library is among the most widely known and best tested libraries. It is available as part of all C++ implementations.
使用庫的代碼比直接使用語言功能的代碼更容易寫，更簡短，更趨向於高層次抽象，而且庫代碼更有可能被測試過。ISO C++標準庫是最有名，經過最好測試的庫之一。它作為C++實現的一部分，可以直接使用。
Example（示例）
<code>auto sum = accumulate(begin(a), end(a), 0.0); // good/<code>
a range version of accumulate would be even better:
使用range的accumulate版本會更好：
<code>auto sum = accumulate(v, 0.0); // better/<code>
but don't hand-code a well-known algorithm:
但是不要試圖硬編碼實現常見算法：
<code>int max = v.size(); // bad: verbose, purpose unstated
double sum = 0.0;
for (int i = 0; i < max; ++i)
sum = sum + v[i];/<code>
Exception（例外）
Large parts of the standard library rely on dynamic allocation (free store). These parts, notably the containers but not the algorithms, are unsuitable for some hard-real-time and embedded applications. In such cases, consider providing/using similar facilities, e.g., a standard-library-style container implemented using a pool allocator.
很大一部分標準庫依靠動態內存分配（自由存儲）。這些部分，主要是容器而非算法，不大適合某些硬實時和嵌入式應用。在這樣的情況下，考慮提供/使用相似的功能。例如從存儲池中分配對象的標準庫風格的容器。
Enforcement（實施建議）
Not easy. ??? Look for messy loops, nested loops, long functions, absence of function calls, lack of use of non-built-in types. Cyclomatic complexity?
不容易。尋找混亂的循環、嵌套循環、長函數、函數調用缺失、很少被使用的內置類型？還是確認圈複雜度？
原文鏈接
https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#es1-prefer-the-standard-library-to-other-libraries-and-to-handcrafted-code
覺得本文有幫助？請分享給更多人。
關注微信公眾號【面向對象思考】輕鬆學習每一天！
面向對象開發，面向對象思考！
閱讀更多 面向對象思考 的文章
