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copied!<p>Returning an array gives some nice benefits:</p> <pre><code>my @foo = get_array(); # Get list and assign to array. my $foo = get_array(); # Get magnitude of list. my ($f1, $f2) = get_array(); # Get first two members of list. my ($f3,$f6) = (get_array())[3,6]; # Get specific members of the list. sub get_array { my @array = 0..9; return @array; } </code></pre> <p>If you return array refs, you'll have to write several subs to do the same work. Also, an empty array returns false in a boolean context, but an empty array ref does not.</p> <pre><code>if ( get_array() ) { do_stuff(); } </code></pre> <p>If you return array refs, then you have to do:</p> <pre><code>if ( @{ get_array_ref() } ) { do_stuff(); } </code></pre> <p>Except if get_array_ref() fails to return a ref, say instead and undef value, you have a program halting crash. One of the following will help:</p> <pre><code>if ( @{ get_array() || [] } ) { do_stuff(); } if ( eval{ @{get_array()} } ) { do_stuff(); } </code></pre> <p>So if the speed benefits are needed or if you need an array ref (perhaps you want to allow direct manipulation of an object's collection element--yuck, but sometimes it must happen), return an array ref. Otherwise, I find the benefits of standard arrays worth preserving.</p> <p><b>Update:</b> It is really important to remember that what you return from a routine is not always an array or a list. What you return is whatever follows the <code>return</code>, or the result of the last operation. Your return value will be evaluated in context. Most of the time, everything will be fine, but sometimes you can get unexpected behavior. </p> <pre><code>sub foo { return $_[0]..$_[1]; } my $a = foo(9,20); my @a = foo(9,20); print "$a\n"; print "@a\n"; </code></pre> <p>Compare with:</p> <pre><code>sub foo { my @foo = ($_[0]..$_[1]); return @foo; } my $a = foo(9,20); my @a = foo(9,20); print "$a\n"; print "@a\n"; </code></pre> <p>So, when you say "return an array" be sure you really mean "return an array". Be aware of what you return from your routines.</p>

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