use strict;
use warnings;

my @list = qw(zero one two three four);
print qq{@list\n};

my @newOrder = (1, 3, 4, 0, 2);
my @newList;

@newList[@newOrder] = @list;
print qq{@newList\n};

@newList = @list[@newOrder];
print qq{@newList\n};

##</code><code>##

zero one two three four
three zero four one two
one three four zero two

##</code><code>##

This code

@newList[@newOrder] = @list;

Means:-

$newList[1] receives $list[0] which is 'zero'
$newList[3] receives $list[1] which is 'one'
$newList[4] receives $list[2] which is 'two'
$newList[0] receives $list[3] which is 'three'
$newList[2] receives $list[4] which is 'four'

whereas this code

@newList = @list[@newOrder];

Means:-

$newList[0] receives $list[1] which is 'one'
$newList[1] receives $list[3] which is 'three'
$newList[2] receives $list[4] which is 'four'
$newList[3] receives $list[0] which is 'zero'
$newList[4] receives $list[2] which is 'two'