How do I get a slice from an array reference?

Question

Let us say that we have following array:

my @arr=('Jan','Feb','Mar','Apr');
my @arr2=@arr[0..2];

How can we do the same thing if we have array reference like below:

my $arr_ref=['Jan','Feb','Mar','Apr'];
my $arr_ref2; # How can we do something similar to @arr[0..2]; using $arr_ref ?

Answer 1

Just slice the reference (the syntax is similar to dereferencing it, see the comments), and then turn the resulting list back into a ref:

my $arr_ref2=[@$arr_ref[0..2]];

Answer 2

my $arr_ref2 = [ @$arr_ref[0..2] ];

Answer 3

To get a slice starting with an array reference, replace the array name with a block containing the array reference. I've used whitespace to spread out the parts, but it's still the same thing:

 my @slice =   @   array   [1,3,2];
 my @slice =   @ { $aref } [1,3,2];

If the reference inside the block is a simple scalar (so, not an array or hash element or a lot of code), you can leave off the braces:

 my @slice =   @$aref[1,3,2];

Then, if you want a reference from that, you can use the anonymous array constructor:

 my $slice_ref = [ @$aref[1,3,2] ];