Compiling REx `^ \s* x '
  size 6 Got 52 bytes for offset annotations.
  first at 2
  rarest char x at 0
  synthetic stclass `ANYOF[\11\12\14\15 x{unicode_all}]'.
     1: MBOL(2)
     2: STAR(4)
     3:   SPACE(0)
     4: EXACT <x>(6)
     6: END(0)