有没有任何众所周知的范例来迭代枚举值？ [英] Is there any well-known paradigm for iterating enum values?

问题描述

我有一些C ++代码，其中声明了以下枚举：

I have some C++ code, in which the following enum is declared:

enum Some 
{
   Some_Alpha = 0,
   Some_Beta,
   Some_Gamma,
   Some_Total
};
int array[Some_Total];

Alpha，Beta和Gamma的值是连续的，我很乐意使用以下循环

The values of Alpha, Beta and Gamma are sequential, and I gladly use the following cycle to iterate through them:

for ( int someNo = (int)Some_Alpha; someNo < (int)Some_Total; ++someNo ) {}

这个循环是确定的，直到我决定改变枚举的声明顺序，使Beta成为第一个值，Alpha成为第二个值。这使循环头无效，因为现在我必须从Beta迭代到Total。
那么，通过枚举迭代的最佳实践是什么？我想遍历所有的值，而不改变每次循环头。我可以想到一个解决方案：

This cycle is ok, until I decide to change the order of the declarations in the enum, say, making Beta the first value and Alpha - the second one. That invalidates the cycle header, because now I have to iterate from Beta to Total. So, what are the best practices of iterating through enum? I want to iterate through all the values without changing the cycle headers every time. I can think of one solution:

enum Some 
{
   Some_Start = -1,
   Some_Alpha,
   ...
   Some_Total
};
int array[Some_Total];

并从（Start + 1）到Total，但看起来很丑陋，在代码中做它。有没有任何众所周知的范例来迭代枚举，或者我只需要修正枚举值的顺序？ （让我们假装，我真的有一些真棒原因改变枚举值的顺序）...

and iterate from (Start + 1) to Total, but it seems ugly and I have never seen someone doing it in the code. Is there any well-known paradigm for iterating through the enum, or I just have to fix the order of the enum values? (let's pretend, I really have some awesome reasons for changing the order of the enum values)...

推荐答案

enum Some
{
   Some_first_ = 0,
   Some_Alpha = Some_first_,
....
   Some_last_
};

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