       (1:0) const                    <--         (1:0) const
             ^                                          ^

       (1:6) nst fn =                 <--         (1:6) nst fn =
                 ^                                          ^

       (1:8) t fn = (a                <--         (1:8) t fn = ar
                 ^                                          ^

      (1:12)  = (arg)                 <--        (1:11) n = arg =
                 ^                                          ^

      (1:15) (arg) =>                 <--        (1:14)  arg => {
                 ^                                          ^

      (1:20)  => {                    <--        (1:18)  => {
                 ^                                          ^

       (2:2)   var [                  <--         (2:2)   var _
               ^                                          ^

      (2:15) ] = arg;                 <--        (2:40) ray(arg,
                 ^                                          ^

      (2:18)  arg;                    <--        (2:43) (arg, 2),
                 ^                                          ^

       (2:7) ar [x, y]                <--         (3:4)     x = _
                 ^                                          ^

       (2:8) r [x, y]                 <--         (3:5)    x = _a
                 ^                                          ^

      (2:10) [x, y] =                 <--         (4:4)     y = _
                 ^                                          ^

      (2:11) x, y] = a                <--         (4:5)    y = _a
                 ^                                          ^

       (3:0) }                        <--         (5:0) };
             ^                                          ^

       (3:1) }                        <--         (5:1) };
              ^                                          ^
