#include <iostream>
 
////////////////////////////////////////////////////////////////////////////////
// ASSUME EVERYTHING IN THIS SECTION IS PART OF AN API AND IS NOT MY OWN CODE...
// I DO NOT HAVE THE SOURCE AND IT CANNOT BE MODIFIED
 
typedef void (*CALLBACK)(std::string message);
 
void call_callback(CALLBACK cb, std::string message) {
    cb(message);
}
 
////////////////////////////////////////////////////////////////////////////////
 
// Our callback takes a string *and* an integer argument
void callback_function(std::string message, int data)
{
    std::cout << message << ' ' << data << '\n';
}
 
int main()
{
    // Using lambdas...
    call_callback([/*empty!*/](std::string message)
    {
        // Call the function as defined in the previous snippet
        callback_function(message, 42);  // Pass the value directly
    }, "Foobar");
}
 

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