在定长数组typedef中使用new [英] Using new with fixed length array typedef

问题描述

如何为固定长度的数组定义typedef，以便也可以新建".以下内容不起作用:

How do I define a typedef for a fixed length array so that I can also 'new'. The following does not work:

typedef double Vector[3];
Vector *v = new Vector; // does not compile

我们正在尝试将一些旧的C代码包装到C ++中，以通用方式处理 float * 和 float(*)[3] .

We are trying to wrap into C++ some old C code which handles float * and float (*)[3] in a generic way.

推荐答案

指向 double [3] 的指针是 double * -这样就可以了:

The pointer to an double[3] is double * - so this will work:

  typedef double Vector[3];
  double *v = new Vector;

但是我建议您不要那样使用-删除数组需要使用array-delete-operator:

But I suggest you don't use it that way - to delete the array you need the array-delete-operator:

  delete[] v;

但是在 new Vector 上，您看不到它是一个数组，因此可能会忘记它.

But on new Vector you don't see it is an array and so it might be forgotten.

Scott Meyers 有效C ++ 处理(强烈建议避免这种情况).所以最好不要在这里使用typedef.

This case is handled (and strongly recommended to avoid) in Scott Meyers Effective C++. So better don't use an typedef here.

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