Gets shift register size
| Lists.au3 _ShiftSize( $aShift ) |
| $aShift | Shift register array as handle |
| integer value | Size of shift register |
| 1 | Not a shift register |
If _ShiftSize( $aMyShift ) > 5 Then $myValue = _ShiftGet( $aMyShift, 5 ) ; get 6th value