bug#61658: 30.0.50; server-eval-at might handle unreadable results better

[Sean Whitton <spwhitton@spwhitton.name>]

Hello,

On Mon 20 Feb 2023 at 07:09PM +02, Eli Zaretskii wrote:

>> From: Sean Whitton <spwhitton@spwhitton.name>
>> Date: Mon, 20 Feb 2023 09:25:34 -0700
>>
>> I use server-eval-at to call a function, in another daemon, which
>> returns a buffer.  So, server-eval-at tries (read "#<buffer *foo*>")
>> which of course fails, and indeed signals an error.
>>
>> I wonder if server-eval-at should return a special value to indicate
>> that the remote computation returned something that is not readably
>> printable?  Or signal a particular error, which the caller might catch?
>
> Why can't you make that function return something more sensible?  Or
> even just nil?

Yes, that is a way to handle cases like this.  I was thinking it might
be better to have

    (define-error 'server-return-invalid-read-syntax
                  "Remote function returned unreadable form"
                  'invalid-read-syntax)

for a more flexible way to handle the situation.

-- 
Sean Whitton