On 26 January 2016 at 12:02, Nathan Hilterbrand <noset...@cotse.net> wrote:
> return wantarray() ? ($a, $b) : [$a, $b];
>
> In a list context, you get back a list.. otherwise you get back a reference
> to a list. Might not be what you want, though.
>
> Works with arrays, too..
>
> my @anarray = (....)
> return wantarray() ? (@anarray) : [@anarray];
I've found pretty much everywhere you'd want that its simpler to just
return either [@anarray] or just \@anarray
Returning lists is cute and all, and returning lists only when in list
context is cute ...
But in practice I find it mostly painful, because you find yourself
needing to "trick" perl into thinking its in list context from time to
time.
And even occasional use of
return (()= function() )
Or whatever the right magic is to force the called function into list
context is just more pain than its worth.
It just seems more practical to always return scalar return values of
some description.
Now, if you want a more useful application of the comma operator, consider:
while ( condition ) {
$x = function(), next if $second_condition
}
Which is equivalent to
while ( condition ) {
$second_condition and $x = function(), next;
}
Which is similar to
while( condition ) {
if ( $second_condition ) {
$x = function();
next;
}
}
But allows a more compact representation ( which matters if you have a
dozen or so such conditions ),
and avoids adding a lexical scope. ( Fun fact, replace "$x =
function(), next;" with "do { $x = function(); next }" and watch
deparse turn it back into an "if" statement :) )
But you can't use "&&" or "and" in the expression, because
"function()" could return a false value, which would prevent the
'next' occurring.
--
Kent
KENTNL - https://metacpan.org/author/KENTNL
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