The multi dispatcher *only* chooses the multi candidate by matching
arguments to parameters. The return type is not considered.
Btw, the syntax for returning an arrayish thing might be: method foo($a,
$b --> Positional) { ... }
Am 19.03.2015 um 23:53 schrieb Darren Duncan:
> I think as a general principle, multi methods should dispatch entirely
> on their parameter signatures, and dispatching on return type is just
> a bad design that leads to trouble. If you want different return
> types for identical parameters, you should give those 2 versions
> different method base names. -- Darren Duncan
>
> On 2015-03-19 3:20 PM, Tom Browder wrote:
>> I need to replace the Perl 5 'wantarray' and think a multi method with
>> differing return types should do it.
>>
>> So I've tried this:
>>
>> multi method foo($a, $b --> {Num,Num}) { #... }
>> multi method foo($a, $b --> Num) { #... }
>>
>> and get errors like:
>>
>> Missing block
>> at Ellipsoid.pm:672
>> ------> ethod to($lat1, $lon1, $lat2, $lon2 --> �{Rat, Rat})
>> from test_ellipsoid.pl:12
>>
>> I've tried parentheses, square brackets, and no grouping characters
>> instead of curly braces but that doesn't change the error.
>>
>> Question:
>>
>> How does one properly provide differing function return type signatures?
>>
>> Thanks.
>>
>> Best,
>>
>> -Tom
>>
>
