program main
  fn label() -> string
    string "standard"
  fn echo(value: string) -> string
    var value
  fn label_len() -> i32
    call std.string.len
      call echo
        string "standard"
  fn main() -> i32
    call std.io.print_string
      call echo
        string "standard"
    call std.io.print_bool
      binary =
        call echo
          string "standard"
        string "standard"
    call std.io.print_i32
      call std.string.len
        string "standard"
    int 0
  test "std string equality"
    binary =
      call echo
        string "standard"
      string "standard"
  test "std string byte length"
    binary =
      call label_len
      int 8