Can I use variadic arguments of different types and can I use V without linking system libs (including vlib)?

[rempas]

Hello everyone, new to V! I want to make 2 questions.

1. Can I use arguments of different types for variadic functions? I tried something like this using any:

fn test_fn(args ...any) {
  for arg in args {
    print("Args: $arg")
  }
}

fn main() {
  test_fn("Hello", "John", 10, true)
}

But I'm getting the following error: error: no known default format for type any. So I suppose this will not work as like the documentation says, this is like void* so it needs to dereference it or something.

2. This is simple, but can I link my program without vlib and without any other system libraries (like when passing "-nostdlib" in TCC/GCC/Clang etc.)?

[JalonSolov]

From v help build-c output:

   -freestanding
      Build the executable without dependency on libc.
      Supported only on `linux` targets currently.

The only way to link without vlib is to not include any calls to anything in vlib... which is impossible, since you will always use the builtin module at a minimum.

[rempas]

Thanks, well I was thinking about creating my own library in assembly so that's why this question

[Wajinn]

Maybe try using generics with the variadic, but the different parameters must be of the same type.

fn test_gen_vari<T>(args ...T) {
	for arg in args  {
		print("Args: $arg ")
	}
}

fn main() {
	test_gen_vari('Hello', 'John', 'Cat')
	test_gen_vari(8, 10, 12, 16, 3)
}

[rempas]

Yeah, I thought about that but I was wondering if someone knew if I can have them be different types from one another. Thanks a lot for your time

[Wajinn]

Yeah, I thought about that but I was wondering if someone knew if I can have them be different types from one another. Thanks a lot for your time

Apologies for not answering this previously, as after posting the generic variadic, a better answer had occurred to me (using sum types) but it had slipped my mind to post it.

type Mixer = int | string | bool   // put the different types or structs that you want

fn main() {
	println(mix_type("Hello", "John", 10, true))  
}

// function is accepting arguments of different types

fn mix_type(list ...Mixer) ([]string, []int, []bool) {
	mut nums := []int{}
	mut strs := []string{}
	mut bools := []bool{}
	
	for value in list {
		if value is int {
			nums << value
		}
		if value is string {
			strs << value
		}
		if value is bool	{
			bools << value
		}
	}
	return strs, nums, bools
}

[rempas]

Don't worry. We are all here in our free time and nobody is obliged to help anyone. So I'm grateful that you found the time to do so now ;)

When it comes to the reply, sum types are great but like I said, to my other post about "printf", I would like to see a way to pass types of different types without having to create a sum type manually. Maybe in the future!