reverse an array

arr_rev

#!/bin/bash

reverse_array() {
    local _array=$1
    shift
    unset $_array
    while (( $# != 0 ))
    do
        printf -v $_array[$#-1] "%s" "$1"
        shift
    done
}

A=(a b c d e f)
reverse_array B "${A[@]}"

echo "${A[@]} 
reversed is 
${B[@]}"