Re: [perl #58236] [TODO][PDD19] make decision on open issue on .return directive in pdd19

["Klaas-Jan Stol" <parrotcode@gmail.com>]

On Sat, Aug 30, 2008 at 11:04 AM, Allison Randal <allison@perl.org> wrote:

> Klaas-Jan Stol (via RT) wrote:
>
>>
>> The parentheses surrounding the arguments are mandatory. Besides making
>> sequence break more conspicuous, this is necessary to distinguish this
>> syntax from other uses of the C<.return> directive that will be probably
>> deprecated.
>>
>>
>> The open issue of the 'probably deprecation' should be decided on; what
>> return directive is meant here that supposedly would be deprecated?
>> Will it? (any need?)
>>
>
> Yes, it will be deprecated, or at least renamed. The C<.return> directive
> without parentheses is an old convention for passing a single return result,
> and must always be sandwiched between  C<.begin_return> and C<.end_return>.


Do you mean this one? (see next)

.begin_return
.return "hi"
.return 42
.return 3.14
.end_return

(which is the same as:   .return ("hi", 42, 3.14)       )
Is the purpose of renaming this to make a clear distinction between the
'.return' directive in this long style of returning and the short one
('.return ()' )   ?


>
> And, there's another C<.return> without parentheses that performs a
> tail-call, invoking a sub or method reusing the same return continuation.
>  This should also be renamed.


Is the purpose to be more explicit on being a tailcall? (in that case, it
could be renamed as ".tailcall" or whatever -- but that's obvious)

>
>
> The only directive that should be named C<.return> is the one that returns
> a value or values (i.e. it's syntactic sugar for a whole collection of
> low-level directives/opcodes).


and this would be:     .return ("hi", 42, 3.14)
right?

>
>
> Allison


kjs