(C ++)将指针传递到模板
我有两个指针。 p1。 p2。
p1和p2都指向不同的类。
这些类有一些类似的方法名称,
,我想调用一个模板函数两次以避免重复代码。
这是我的函数:
I have two pointers. p1. p2.
p1 and p2 both point to different classes.
The classes have some similar method names,
and I'd like to call a template function twice to avoid repeated code.
Here is my function:
template <class T>
void Function(vector<T> & list, T* item, const string & itemName)
$ b b
看到中间参数,项目..是我的签名应该怎么样,如果我想要项目改变?
see that middle paramater, "item".. is that how my signature should look if I want the item changed?
..或者我应该将其作为
T *&项目
..or should I pass it as
T* & item
..或者我应该将其作为
T **项目传递
..or should I pass it as
T** item
编译器允许很多事情滑动,但是当我去绑定一切它打破。
the compiler is letting a lot of things slide, but then when I go to bind everything it breaks.
如何使用我的指针调用该函数? >
关于铸造的东西?我试过了一切:\
How do I call that function using one of my pointers?
something about casting?? I've tried everything :\
您应该可以这样调用您的代码:
You should be able to call your code like this:
template <class T>
void Function(std::vector<T> & list, T* item, const std::string & itemName)
{
list.push_back(T());
if (item != NULL)
item->x = 4;
}
struct A
{
int x;
};
struct B
{
double x;
};
A a;
B b;
std::vector<A> d;
std::vector<B> i;
Function(d, &a, "foo");
Function(i, &b, "bar");
注意,通过引用和指针传递参数有稍微不同的含义。指针可以为NULL,请参见在C ++中通过引用传递指针是否有好处?。
Note that passing a parameter by reference and by pointer has slightly different meaning, e.g. pointers can be NULL, see Are there benefits of passing by pointer over passing by reference in C++?.
我想知道是否需要传递 item
通过指针和
列表
通过(非const)引用。
I wonder if it's desired to pass item
by pointer and list
by (non-const) reference.