Request for disclosure of technical implementation details

when
fn init {
  println("whats_up")
}
i get wat
(func $printc (import "spectest" "print_char") (param $i i32))

(func $moonbit.output_string (param $str (ref $moonbit.string))
 (local $counter i32)
 (loop $loop
  (if (i32.lt_s (local.get $counter) (array.len (local.get $str)) )
   (then
    (call $printc
     (array.get_u $moonbit.string (local.get $str) (local.get $counter)))
    (local.set $counter (i32.add (local.get $counter) (i32.const 1)))
    (br $loop)
    )
  (else))))

I don’t think “spectest” “print_char” is standard or common
This took me a lot of time

Are there any other similar APIs for external interaction that have this kind of situation?

只有输入输出相关以及Js_string相关的API。