Binding and Function Templates

Yes, std::bind() can be used with function templates. When binding a function template, you need to provide the template arguments explicitly or let the compiler deduce them based on the bound arguments.

Consider the following example:

1#include <functional>
2#include <iostream>
3#include <string>
4
5template <typename T>
6void PrintValue(T Value) {
7  std::cout << Value << '\n';
8}
9
10int main() {
11  auto PrintInt{std::bind(
12    PrintValue<int>, std::placeholders::_1)};
13
14  auto PrintString{std::bind(
15    PrintValue<std::string>,
16    std::placeholders::_1)};
17
18  PrintInt(42);
19  PrintString("Hello");
20}

142
2Hello

In this example, we have a function template PrintValue that takes a single argument of any type T and prints its value. When binding PrintValue using std::bind, we explicitly provide the template argument (int or std::string) to specialize the function template. The resulting PrintInt and PrintString functors are bound to the specialized versions of PrintValue for int and std::string respectively.

However, using std::bind to deduce the template arguments directly is not straightforward and often not possible. Instead, you can use a lambda function to achieve the desired behavior with template argument deduction:

1#include <iostream>
2#include <string>
3
4template <typename T>
5void PrintValue(T Value) {
6  std::cout << Value << '\n';
7}
8
9int main() {
10  auto PrintValueAuto{
11    [](auto Value) { PrintValue(Value); }
12  };
13
14  PrintValueAuto(42);
15  PrintValueAuto("Hello");
16}

142
2Hello

In this case, we use a lambda function that takes an auto parameter. The compiler deduces the type of the parameter when the lambda is called, allowing PrintValue to be called with the correct template argument. This approach provides the flexibility of template argument deduction without the need for std::bind in this context.

Binding function templates allows you to create reusable functors that can work with different types, providing flexibility and generic programming capabilities.