Why does compile discard multiple values?

Why does compile discard multiple values?

[Jean Abou Samra]

Hi,

See:

$ guile3.0
GNU Guile 3.0.7
Copyright (C) 1995-2021 Free Software Foundation, Inc.

Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
This program is free software, and you are welcome to redistribute it
under certain conditions; type `,show c' for details.

Enter `,help' for help.
scheme@(guile-user)> (eval '(values 1 2) (current-module))
$1 = 1
$2 = 2
scheme@(guile-user)> (use-modules (system base compile))
scheme@(guile-user)> (compile '(values 1 2) #:env (current-module))
$3 = 1


Is it expected that compile doesn't cope with a return of
multiple values?

I can work around that using

((compile `(lambda () ,my-form)
           #:env (current-module)))

but I would have expected it to work out of the box. Should
I raise it on the bug tracker?

Thanks,
Jean

Re: Why does compile discard multiple values?

[Jean Abou Samra]

Le 10/08/2022 à 15:01, Jean Abou Samra a écrit :
> I can work around that using
>
> ((compile `(lambda () ,my-form)
>           #:env (current-module)))


Ugh, no, I can't. The form might be a define.

Does anybody know of a workaround?

Thanks,
Jean

Re: Why does compile discard multiple values?

[Jean Abou Samra]

Le 10/08/2022 à 15:11, Jean Abou Samra a écrit :
>
>
> Le 10/08/2022 à 15:01, Jean Abou Samra a écrit :
>> I can work around that using
>>
>> ((compile `(lambda () ,my-form)
>>           #:env (current-module)))
>
>
> Ugh, no, I can't. The form might be a define.
>
> Does anybody know of a workaround?



OK, digging into the implementation, I found

scheme@(guile-user)> (use-modules (system vm loader))
scheme@(guile-user)> ((load-thunk-from-memory (compile '(values 1 2) 
#:to 'bytecode #:env (current-module))))
$1 = 1
$2 = 2

If someone has a better workaround, I'm still interested.

Re: Why does compile discard multiple values?

[Maxime Devos]

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On 10-08-2022 15:01, Jean Abou Samra wrote:
> Hi,
>
> See:
>
> $ guile3.0
> GNU Guile 3.0.7
> Copyright (C) 1995-2021 Free Software Foundation, Inc.
>
> Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
> This program is free software, and you are welcome to redistribute it
> under certain conditions; type `,show c' for details.
>
> Enter `,help' for help.
> scheme@(guile-user)> (eval '(values 1 2) (current-module))
> $1 = 1
> $2 = 2
> scheme@(guile-user)> (use-modules (system base compile))
> scheme@(guile-user)> (compile '(values 1 2) #:env (current-module))
> $3 = 1
>
>
> Is it expected that compile doesn't cope with a return of
> multiple values? [...]

Sounds like a bug to me (it's not a documented limitation). I would 
report it.

Greetings,
Maxime


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Re: Why does compile discard multiple values?

[Jean Abou Samra]

Le 10/08/2022 à 20:08, Maxime Devos a écrit :
>
> On 10-08-2022 15:01, Jean Abou Samra wrote:
>> Hi,
>>
>> See:
>>
>> $ guile3.0
>> GNU Guile 3.0.7
>> Copyright (C) 1995-2021 Free Software Foundation, Inc.
>>
>> Guile comes with ABSOLUTELY NO WARRANTY; for details type `,show w'.
>> This program is free software, and you are welcome to redistribute it
>> under certain conditions; type `,show c' for details.
>>
>> Enter `,help' for help.
>> scheme@(guile-user)> (eval '(values 1 2) (current-module))
>> $1 = 1
>> $2 = 2
>> scheme@(guile-user)> (use-modules (system base compile))
>> scheme@(guile-user)> (compile '(values 1 2) #:env (current-module))
>> $3 = 1
>>
>>
>> Is it expected that compile doesn't cope with a return of
>> multiple values? [...]
>
> Sounds like a bug to me (it's not a documented limitation). I would 
> report it.

Thanks, done:

https://debbugs.gnu.org/cgi/bugreport.cgi?bug=57123