Re: [Csnd-dev] [EXTERNAL] Re: [Csnd-dev] expression with multiple outputs

PR is here: https://github.com/csound/csound/pull/2285

On Mon, Sep 22, 2025 at 9:14 PM Victor Lazzarini <
[email protected]> wrote:

> Sounds great
> Prof. Victor Lazzarini
> Maynooth University
> Ireland
>
> On 22 Sep 2025, at 13:59, Eduardo Moguillansky <
> [email protected]> wrote:
>
> 
> I can add a variant of pan2, if needed
>
> On Mon, Sep 22, 2025 at 2:45 PM joachim heintz <[email protected]>
> wrote:
>
>> yes what you say is what i had in mind:
>> "There could be a section in the manual on inlined opcodes giving
>> examples where it can be noted that only opcodes with one output may be
>> inlined."
>>
>> in the case of pan2: might it be an idea to add an array output, as
>> eduardo mentioned?
>>
>> On 22/09/2025 20:42, Victor Lazzarini wrote:
>> > What do you have in mind in terms of documentation?
>> >
>> > There could be a section in the manual on inlined opcodes giving
>> examples where it can be noted that only opcodes with one output may be
>> inlined.
>> >
>> > Note that this is a common approach in other languages that have
>> multiple outputs. In Python tuples are used to handle this,
>> >
>> > def fun(): return 1, 2
>> >
>> > fun()
>> > (1,2)
>> >
>> > def fun2(a,b): return a, b
>> >
>> > fun2(fun())
>> > TypeError: fun2() missing 1 required positional argument 'b'
>> >
>> > fun2(fun()[0], fun()[1])
>> > (1,2)
>> >
>> > In Csound we can do similarly with arrays.
>> >
>> > Prof. Victor Lazzarini
>> > Maynooth University
>> > Ireland
>> >
>> >> On 21 Sep 2025, at 23:13, joachim heintz <[email protected]> wrote:
>> >>
>> >> ok --- thanks to all for the explanations and thoughts.
>> >> i wonder where is a good place to document it.
>> >> or is it already anywhere documented?
>> >>
>> >>> On 22/09/2025 04:41, Victor Lazzarini wrote:
>> >>> It's a can of worms. I have discussed this with Steven and we
>> concluded it's a bad idea.
>> >>> Prof. Victor Lazzarini
>> >>> Maynooth University
>> >>> Ireland
>> >>>>> On 21 Sep 2025, at 19:25, Hlöðver Sigurðsson <[email protected]>
>> wrote:
>> >>>>
>> >>>> 
>> >>>> in theory the out could infer the [a,a] after I finish this behemoth
>> change regarding struct arrays I could take a look at this
>> >>>>
>> >>>>> On Sun, 21 Sept 2025 at 17:17, Victor Lazzarini <000010b17ddd988e-
>> [email protected] <mailto:000010b17ddd988e-dmarc-
>> [email protected]>> wrote:
>> >>>>
>> >>>>     No, we don't have that syntax and we have decided a while ago
>> that
>> >>>>     we would not try to implement it.
>> >>>>
>> >>>>     So in summary, a multi-output opcode cannot be used inline like
>> this.
>> >>>>
>> >>>>     Prof. Victor Lazzarini
>> >>>>     Maynooth University
>> >>>>     Ireland
>> >>>>
>> >>>>     > On 21 Sep 2025, at 14:35, joachim heintz <[email protected]
>> >>>>     <mailto:[email protected]>> wrote:
>> >>>>     >
>> >>>>     > *Warning*
>> >>>>     >
>> >>>>     > This email originated from outside of Maynooth University's
>> Mail
>> >>>>     System. Do not reply, click links or open attachments unless you
>> >>>>     recognise the sender and know the content is safe.
>> >>>>     >
>> >>>>     > my assumption was that if out(a1,a2) works, it should also work
>> >>>>     if the
>> >>>>     > two arguments are the outputs of an expression, like here.
>> >>>>     >
>> >>>>     >
>> >>>>     >> On 21/09/2025 22:28, Eduardo Moguillansky wrote:
>> >>>>     >> pan2 returns two outputs, not an array. So I would say that
>> it is a
>> >>>>     >> limitation in the sense that for that to work one would need
>> to
>> >>>>     add a
>> >>>>     >> variant of pan2 which returns an array.
>> >>>>     >>
>> >>>>     >> On Sun, Sep 21, 2025 at 3:18 PM joachim heintz
>> >>>>     <[email protected] <mailto:[email protected]>
>> >>>>     >> <mailto:[email protected] <mailto:[email protected]>>>
>> wrote:
>> >>>>     >>
>> >>>>     >>    nchnls = 2
>> >>>>     >>    0dbfs = 1
>> >>>>     >>
>> >>>>     >>    instr 1
>> >>>>     >>        sound:a = pinkish(.1)
>> >>>>     >>        out(pan2(sound,random:i(0,1)))
>> >>>>     >>    endin
>> >>>>     >>    schedule(1,0,1)
>> >>>>     >>
>> >>>>     >>    error: opcode 'pan2' for expression with arg types ai
>> >>>>     returns out-args
>> >>>>     >>    != 1, line 14
>> >>>>     >>
>> >>>>     >>    is this a limitation, or is it supposed to work?
>> >>>>     >>
>> >>>>     >>    thanks -
>> >>>>     >>             joachim
>> >>>>     >>
>> >>>>
>>
>