Nice trick. I like it as a sort of answer to LISP-like linked lists without having to resort to 2-element array references:
my @array = qw(a b c d);
my $r = sub { \@_ }->(@array);
my $a = cdr($r);

print "arr: @array\n";
print "a: @$a\n";
print "r: @$r\n";
$array[2]="hello";
print "arr: @array\n";
print "a: @$a\n";
print "r: @$r\n";

sub cdr {
  my $r = shift;
  my $a = sub { \@_ }->(@$r);
  shift @$a;
  $a;
}

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In reply to Re: Non-destructive array processing by runrig
in thread Non-destructive array processing by Juerd

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