How to Create Function Aliases in C 11?

Function Aliasing in C 11

In C 11, aliasing classes using the using directive is straightforward. However, creating aliases for functions proves more challenging.

Problem:

Consider the following namespace and function declaration:

<code class="cpp">namespace bar {
    void f();
}</code>

Attempting to alias the function with using g = bar::f; will result in an error, as "f" is not a type in the "bar" namespace.

Clean Solution with Perfect Forwarding:

To create a function alias, perfect forwarding can be used:

<code class="cpp">template<typename... Args>
auto g(Args&&... args) -> decltype(f(std::forward<Args>(args)...)) {
    return f(std::forward<Args>(args)...);
}</code>

This solution ensures that g forwards all arguments to f correctly, even if f is overloaded or a function template.

Definition of Alias:

An alias, or B, is an entity of substance A that ensures that any replacement of B in the source code for any usage (not including declarations or definitions) of A will result in unaltered compiled code.

Example:

After defining the g alias, the following code will call f through the alias:

<code class="cpp">g(1, 2, 3); // Calls bar::f(1, 2, 3);</code>

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