Addrcalls

Addrcalls are low-level calls to a function address. An addrcall takes address to the destion function and calls it. It is different from Jule function calls. For anonymous functions, Jule runtime may store implicit data for closures and etc. Addrcalls just passes arguments.

Jule Calls vs Addrcalls

Jule Call	Addrcall
Based on pointer with function type wrapper	Based on raw pointer/memory address
Safety checks before call, like nil pointer	No safety checks, immediately jumps to function
May be implicit arguments like closure data	No hidden arguments, just explicit ones
Explicit sign, static type analysis	Implicit sign, flexible, no static type analysis
Suitable for Jule functions and interoperability	Suitable for syscalls, low-level calls, advanced interoperability

Example Use

use "std/sys"

cpp let write: *unsafe

fn main() {
	m := "hello, world"
	sys::Addrcall(uintptr(cpp.write), i32(1), &m[0], len(m))
}

In the example above, the write function accessed with C is linked as if it were a pointer. Technically, functions are pointers. Then, its address is taken as an integer with uintptr and called with Addrcall. A simple Hello, world example.

The Addrcall function prototypes the called function according to the arguments. Remember, the types must be correct. Any type mismatch can cause various problems.

Return Values

Any Addrcall is void by default. So does not return value. If your function return value, you can specify it with the single generic type.

For example:

use "std/sys"

cpp let write: *unsafe

fn main() {
	m := "hello, world\n"
	n := sys::Addrcall[i32](uintptr(cpp.write), i32(1), &m[0], len(m))
	println(n)
}

In the example above is basically same as the previous example. But it reads return value of the write function.