我继承了一个大型 Visual Studio 6 C++ 项目，需要将其翻译为 VS2005。一些类定义了operator<和运算符[]，但不在声明中指定返回类型。 VS6允许这样做，但VS2005不允许。
我知道 C 标准指定普通函数的默认返回类型是 int，并且我假设 VS6 可能遵循这一点，但这也适用于 C++ 运算符吗？或者 VS6 可以自己计算出返回类型吗？
例如，代码定义了一个如下所示的自定义字符串类：
class String {
char arr[16];
public:
operator<(const String& other) { return something1 < something2; }
operator[](int index) { return arr[index]; }
};
VS6 是否会简单地将两者的返回类型都设置为 int，或者它会足够聪明地计算出operator[] 应该返回 char 且operator<;应该返回一个 bool （而不是始终将两个结果都转换为 int ）？
当然，我必须添加返回类型以使此代码兼容 VS2005 C++，但我想确保指定与以前相同的类型，以免立即更改程序行为（我们目前正在寻求兼容性；我们'稍后将标准化）。
I've inherited a large Visual Studio 6 C++ project that needs to be translated for VS2005. Some of the classes defined operator< and operator[], but don't specify return types in the declarations. VS6 allows this, but not VS2005.
I am aware that the C standard specifies that the default return type for normal functions is int, and I assumed VS6 might have been following that, but would this apply to C++ operators as well? Or could VS6 figure out the return type on its own?
For example, the code defines a custom string class like this:
class String {
char arr[16];
public:
operator<(const String& other) { return something1 < something2; }
operator[](int index) { return arr[index]; }
};
Would VS6 have simply put the return types for both as int, or would it have been smart enough to figure out that operator[] should return a char and operator< should return a bool (and not convert both results to int all the time)?
Of course I have to add return types to make this code VS2005 C++ compliant, but I want to make sure to specify the same type as before, as to not immediately change program behavior (we're going for compatibility at the moment; we'll standardize things later).
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默认情况下，
operator<返回一个bool。operator[]默认返回int（我认为），但几乎可以肯定应该将其更改为返回集合包含的任何内容。对于上面给出的字符串示例，这将是char或wchar_t。operator<returns aboolby default.operator[]returnsintby default (I think), but it should almost certainly be changed to return whatever the collection contains. For the String example you gave above, that would be acharorwchar_t.