>>>>> "BM" == Brandon McCaig <bamcc...@gmail.com> writes:
BM> On Thu, Feb 10, 2011 at 10:20 PM, Uri Guttman <u...@stemsystems.com>
wrote:
>> this is all well documented. and i posted an explanation earlier in the
>> thread.
BM> I didn't realize this was an existing thread. In Google Mail it
BM> appeared as a new thread.
>> BM> sub test3
>> BM> {
>> BM> my @empty_array = ();
>>
>> BM> return @empty_array;
>> BM> }
>>
>> that is very different than the above two.
BM> The point was to compare the results. It wasn't supposed to be the same.
:-/
but returning an array was never mentioned before. it is a very
different beast.
>> have it by definition. the array is returned in scalar context and it
>> has zero elements so the return value is 0. the rule is very simple: the
>> return expression is evaluated in the caller's context. it is just as if
>> you took the return expression and put it in an assignment.
BM> I thought that Perl couldn't return arrays. I thought it could only
BM> return scalars and lists. And so I believed that returning an empty
BM> array would in fact return an empty list. The point was for that empty
BM> list to become 0 in scalar context, which could be compared to the
BM> subroutine that returned with `return ();`. The fact that the `return
BM> ();` example returned undef instead indicated to me that `return ();`
BM> was equivalent to `return;`.
as is documented and as i said. the () are meaningless there. they just
group. as i keep saying parens in general in perl are for grouping and
syntax and not much else (to most newbie's surprise). they don't make
lists. they are useful to delineate where a list is (that is grouping).
>> these do the same thing:
>>
>> $scalar = test1() ;
>> $scalar = () ;
BM> I would have expected 0 from the latter of the two. :-/ I guess I
BM> don't understand how Perl works after all. Better I find out this way
BM> though. :P
undef is not 0.
uri
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