Re: Concurrency via isolated process/thread

[Ihor Radchenko]

Eli Zaretskii <eliz@gnu.org> writes:

>> > That is already a problem, as long as we are talking about leaving
>> > most of Emacs application code intact.  How do you ensure only the
>> > main thread can process input and display?  A non-main thread can
>> > easily call some function which prompts the user, e.g., with
>> > yes-or-no-p, or force redisplay with sit-for, and what do you do when
>> > that happens?
>> 
>> To signal an error.
>
> Great! that means in practice no existing Lisp program could ever run
> in a non-main thread.  It isn't a very practical solution.
>
> Besides, non-main threads do sometimes legitimately need to prompt
> the user.  It is not a programmer's error when they do.

As an alternative async threads can be temporarily changed to
cooperative in such scenario.

They will already have to wait synchronously when consing new objects
anyway.

-- 
Ihor Radchenko // yantar92,
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