Hello ozboomer,

Perl’s built-in sort function accepts a custom subroutine to do the comparisons. Here is one using the first_index function from List::MoreUtils:

use strict;
use warnings;
use Data::Dump;
use List::MoreUtils qw( first_index );

my  @fruit   = qw( APPLE ORANGE PEACH GRAPE BANANA PINEAPPLE );
my  @subset  = qw( PINEAPPLE GRAPE APPLE );
#my @subset  = qw( PINEAPPLE GRAPE PEACH BANANA APPLE ORANGE );
my  @results = sort fruit_order @subset;
dd \@results;

sub fruit_order
{
    (first_index { $a eq $_ } @fruit) <=>
    (first_index { $b eq $_ } @fruit);
}
[download]

Output:

18:00 >perl 2017_SoPW.pl
["APPLE", "GRAPE", "PINEAPPLE"]

18:04 >
[download]

Hope that helps,