  (1:0-6) const fn =              <--    (1:0-6) const fn =
          ^^^^^^                                 ^^^^^^

  (1:6-8) nst fn = (              <--    (1:6-8) nst fn = a
              ^^                                     ^^

 (1:8-12) t fn = (arg)            <--   (1:8-11) t fn = arg 
              ^^^^                                   ^^^

(1:12-15)  = (arg) =>             <--  (1:11-14) n = arg => 
              ^^^                                    ^^^

(1:15-20) (arg) => {              <--  (1:14-18)  arg => {
              ^^^^^                                  ^^^^

(1:20-21)  => {                   <--  (1:18-19)  => {
              ^                                      ^

 (2:2-15)   var [x, y] = arg;     <--    (2:2-6)   var _arg
            ^^^^^^^^^^^^^                          ^^^^

 (2:2-15)   var [x, y] = arg;     <--   (2:6-10) var _arg = b
            ^^^^^^^^^^^^^                            ^^^^

 (2:2-15)   var [x, y] = arg;     <--  (2:10-13) _arg = babe
            ^^^^^^^^^^^^^                            ^^^

 (2:2-15)   var [x, y] = arg;     <--  (2:13-25) g = babelHelpers.sli
            ^^^^^^^^^^^^^                            ^^^^^^^^^^^^

 (2:2-15)   var [x, y] = arg;     <--  (2:25-26) pers.slic
            ^^^^^^^^^^^^^                            ^

 (2:2-15)   var [x, y] = arg;     <--  (2:26-39) ers.slicedToArray(arg
            ^^^^^^^^^^^^^                            ^^^^^^^^^^^^^

 (2:2-15)   var [x, y] = arg;     <--  (2:39-40) rray(arg,
            ^^^^^^^^^^^^^                            ^

(2:15-18) ] = arg;                <--  (2:40-43) ray(arg, 2)
              ^^^                                    ^^^

(2:18-18)  arg;                   <--  (2:43-48) (arg, 2),
             ><                                      ^^^^^

  (2:7-8) ar [x, y]               <--    (3:4-5)     x = _
              ^                                      ^

 (2:8-10) r [x, y] =              <--    (3:5-8)    x = _arg
              ^^                                     ^^^

 (2:8-10) r [x, y] =              <--   (3:8-12) x = _arg[0],
              ^^                                     ^^^^

 (2:8-10) r [x, y] =              <--  (3:12-16) _arg[0],
              ^^                                     ^^^^

(2:10-11) [x, y] =                <--    (4:4-5)     y = _
              ^                                      ^

(2:11-19) x, y] = arg;            <--    (4:5-8)    y = _arg
              ^^^^^^^^                               ^^^

(2:11-19) x, y] = arg;            <--   (4:8-12) y = _arg[1];
              ^^^^^^^^                               ^^^^

(2:11-19) x, y] = arg;            <--  (4:12-16) _arg[1];
              ^^^^^^^^                               ^^^^

  (3:0-1) }                       <--    (5:0-1) };
          ^                                      ^

  (3:1-1) }                       <--    (5:1-2) };
          ><                                      ^
