Looks to me like the second example is wrong. First, understand that the first example really is a shortcut for

my $myarray = shift @_;
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Once you see that, it makes sense that $myarray contains the first element in @_ (which is the first argument passed to the subroutine).

So, the second example would assign a '1' to $myarray, because when you assign an array to a scalar, you get the number of the elements of the array.

Here is a test script for you to play with:

use strict;
use Data::Dumper;

sub foo {
    my $ref = shift;
    print Dumper $ref;
}


sub bar {
    my $ref = @_;
    print Dumper $ref;
}

my @ary = qw(a b c d e f);
my $ref = [ qw(a b c d e f) ];

foo(@ary);
foo($ref);
bar(@ary);
bar($ref);
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 perl -le '$x="jeff";$x++ for(0..4482550);print $x'
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