Yes, you are right about the extra brackets. But the rest is more complicated. 
 
    my ($command, $first, $second) = (split) [0, 1, -1];
    $second = $first unless defined $second;

[download]
will only "work" because of a bug in Perl. It's still present in perl5.6.1, however, it's fixed in the development release. Index -1 should always be the last element. Regardless of how many elements there are in the list. The bug, however, is that when indexing over the result of a split, you cannot "reuse" elements. Repeating indexes result in undef. And when there are only two elements in the split, 1 and -1 will point to the same element - making $second undefined.

With the development version of Perl, you could just do: 

    my ($command, $first, $second) = (split) [0, 1, -1];

[download]
and $second will be the right thing: the last element of the split. Hence, if there are just two items, $second will be the same as $first, just what you want.

Luckely, the line 

 
    $second = $first unless defined $second;

[download]
won't harm you in the development version, as $second will be defined, so no assignment is done.

-- Abigail

In reply to Re: split'ing lines with variable number of fields by Abigail
in thread split'ing lines with variable number of fields by IraTarball

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