提高::绑定和放大器;加强与部分ARGS ::功能 [英] boost::bind & boost::function with partial args

问题描述

我后你什么，我想要做一个例子，这是比较容易通过这种方式来解释

I post you an example of what I want to do, that is easier to explain in this way

    void myPrinter(const char* text, int number){            
            printf("\n%s %d\n", text, number);
        }

    int main() {

        char *someText="test";        

       boost::function<void(int my_number)> functionWithSavedArgs = boost::bind(&myPrinter, someText, ?????);

       //then I have to call my function with saved args and give to it only variable "number" like:
       int myBeautifulNumber = 2012;
       functionWithSavedArgs(myBeautifulNumber);
       // echo: test 2012
     }

任何想法？

推荐答案

跳过这样的说法。

   boost::function<void(int my_number)> functionWithSavedArgs
        = boost::bind(&myPrinter, someText);

这只是绑定第一个参数。

This binds only the first argument.

如果你想绑定只有第二个，你需要一个占位符：

If you wanted to bind only the second one, you would need a placeholder:

   boost::function<void(int my_number)> functionWithSavedArgs
         = boost::bind(&myPrinter, _1, someNumber);

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