Perl has an easy way to create an array with elements aliased to arbitrary other things: subroutine parameters.

use Data::Dumper;

my @dna = qw(A T T G C);

print Dumper \@dna;

my $view = sub { \@_ }->(@dna[1,2]);

$view->[0] = 'x';
$view->[1] = 'x';

print Dumper \@dna;

$view = sub { \@_ }->( $dna[4], @$view[1..$#$view] );

$view->[0] = 'y';
$view->[1] = 'y';

print Dumper \@dna;
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