4.2. Use of "shift" in Functions

One can use the shift function to extract arguments out of the argument array. Since this use is so common, then simply typing shift without any arguments will do exactly that.

Here is the split program from the previous slide, which was re-written using shift:

use strict;
use warnings;

sub mysplit
{
    my $total = shift;
    my $num_elems = shift;
    my @accum = @_;
    my (@ret, @new_accum);


    if ($num_elems == 1)
    {
        push @accum, $total;
        print join(",", @accum), "\n";

        return;
    }

    for(my $a=0;$a<=$total;$a++)
    {
        @new_accum = (@accum, $a);
        mysplit($total-$a, $num_elems-1, @new_accum);
    }
}

mysplit(10,3);