Drew Adams via "Bug reports for GNU Emacs, the Swiss army knife of text
editors" <bug-gnu-emacs@gnu.org> writes:
> I wrote:
>
>> When Emacs dings it's typically due to a user error.
>>
>> Where do you see the error message? In the echo area.
>>
>> Putting the attention-grabbing "flash" or whatever
>> in the echo area draws your attention to it, where
>> you see the msg telling you what happened.
>>
>> Why draw or keep the user's attention _away_ from
>> that message? The user error might have little or
>> nothing to do with the text at the cursor of the
>> selected window.
>>
>> Draw the user's attention _from_ there to the helpful
>> message.
>
> `visible-bell' has been around forever. Flashing
> the entire frame (or as the Emacs manual says, "the
> whole screen") is overkill, and it doesn't direct
> your attention to the error message. Similar problem
> with the alternatives I think you're considering,
> even if they're less overkill than `visible-bell'
> behavior.
>
> A modest attention-grabber, out of the way in the
> echo area is better, IMO.
I think these features could coexist together, it wouldn't hurt.
Flash the mode (or header) line for bell it is something that people
have wanted to have, see packages such as mode-line-bell, doom-themes
(both in MELPA), and nano-bell.
I made my own implementation of echo-bell:
I think the term duration is better than length when describing time intervals.
I still prefer the unwind-protected sit-for method that guarantees the remaps are removed to the one with the timer where I've experienced errors intervening with a race condition creating new cookies that are not removed. Try mashing C-g with your timer implementation and you'll see it.
I also prefer the implementation that I proposed that takes a list of faces to flash rather than hard-code an assumption about what users want to flash. Then this isn't tied to the mode line if that's not what people want. Is a new face really necessary just to implement a flash? The implementation I proposed allows the user to specify any face attributes to define what they want for a flash. I wouldn't use this feature without it being more reliable and flexible.