Re: master d014a5e: Use fixed-pitch font for display-line-numbers

[Yuri Khan <yuri.v.khan@gmail.com>]

On Thu, Jul 13, 2017 at 10:57 PM, Eli Zaretskii <eliz@gnu.org> wrote:

>> Maybe, but the name ‘fixed-pitch-serif’ suggests a particular
>> presentation (a serif font), while ‘fixed-pitch’ does not.
>
> AFAIU, fixed-pitch just means Sans Serif, so it is also a particular
> presentation in that sense.

The name ‘fixed-pitch’ literally means only the fixedness of pitch and
says nothing about presence or absence of serifs.

>> Based on face names alone, I would expect that it is more likely for
>> ‘fixed-pitch’ to be the same family as ‘default’ than for
>> ‘fixed-pitch-serif’.
>
> What is that expectation based on?

Names, and names alone. Neither ‘fixed-pitch’ nor ‘default’ say
anything about serifs, therefore, in the default case when ‘default’
wants to be monospaced, they should be identical. That is what the
principle of least astonishment dictates.


I have also just read Bug#19889 which was the motivation for
‘fixed-pitch-serif’: A face that is monospace but intentionally
different from the default. (Brrr.) Arguably, if that was the intent,
then it is poorly named. Should have been ‘fixed-pitch-alternative’ or
‘fixed-pitch-2’. Anyway, with that history, it should not be used for
line numbers, which should strive to use the same typeface as default
if at all possible.

It would be acceptable, from the theoretical point, to use the UI font
(the same that is used for menus) for line numbers. But that is most
likely proportional. Having three different typefaces for the buffer
text, line numbers, and menu bar, is just offensive.

> And fixed-pitch definitely doesn't yield the
> same font as the default face on my system.

I would suggest that is a bug.