program main
  fn label() -> string
    string "slovo" : string
  fn echo(value: string) -> string
    var value : string
  fn local_label() -> string
    local let value : unit
      call label : string
    var value : string
  fn label_len() -> i32
    call string_len : i32
      call local_label : string
  fn main() -> i32
    call print_string : unit
      call local_label : string
    call label_len : i32
  test "string literal equality"
    binary = : bool
      string "slovo" : string
      string "slovo" : string
  test "string parameter equality"
    binary = : bool
      call echo : string
        string "runtime" : string
      string "runtime" : string
  test "string call return equality"
    binary = : bool
      call local_label : string
      string "slovo" : string
  test "string byte length"
    binary = : bool
      call label_len : i32
      int 5 : i32