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Comment by fctorial | Hacker News Reader

What you actually want is function overloading, which C can't support since C functions map directly to elf symbols, and all assembly functions are vararg with all arguments being WORDs. (That's how it is in elf, *nix and x64, don't know much about other platforms)

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You don't need a vtable for overloading; that is just runtime polymorphism ("ad hoc polymorphism".

Function overloading can be done compile time, eg., parametrically:

    add(3.0, 1.0) -> compile to add_float32_float32
    add(1, 2)  -> compile to add_int32_int32

As I said, `add` function in C maps to a symbol named `add` in assembly. You're demangling the function name, which is what C++ does.

Sure, you're right.

I guess we'd need C to have a special syntax to compile in something like a vtable

add_f32_f32(x, y) calls add(MAGIC_NO, x, y)

and add has a big switch on MAGIC_NO for selecting implementation...

You'd need a keyword for this, "multi int add(int a, int b) ..."

such complications where this is what C++ gives you natively

_Generic macros provide similar functionality to function overload(which in C++ involves name mangling, that will never be accepted for C) https://en.cppreference.com/w/c/language/generic

Clang has C function overloading. I use it in a reasonable sized code base. It really cleans up the source code, you end up skipping a lot of the type name or package name parts of function names which accumulate in larger projects leaving a much cleaner source to read. 100% recommend.

Not necessarily, they could standardize it as a syntax like _Generic, to make it so that the user has to choose a unique name for each function, but then they can all be called by a common name.

In C++, name mangling is used to solve this issue

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