Note that there is a difference in meaning between
davorg's reply and
BrowserUk's which depends on whether you slice the new or the original array. The following illustrates this
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};
This produces
zero one two three four
three zero four one two
one three four zero two
It is difficult to tell one zero or one from another, hence the change in list values :)
Cheers,
JohnGG
Update: Here is a clearer explanation of what is happening
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'
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