list
  ident module
  ident tests
list
  ident fn
  ident add
  list
    list
      ident a
      ident i32
    list
      ident b
      ident i32
  arrow ->
  ident i32
  list
    ident +
    ident a
    ident b
list
  ident test
  string "add works"
  list
    ident =
    list
      ident add
      int 2
      int 3
    int 5
list
  ident fn
  ident main
  list
  arrow ->
  ident i32
  int 0