On Sun, Nov 21, 2021 at 12:18 PM Lars Ingebrigtsen <
larsi@gnus.org> wrote:
Eli Zaretskii <eliz@gnu.org> writes:
> They are numbers, so they can change the width because different
> digits have different width.
No, they don't (in the vast majority of proportional fonts).
You're both right.
More specifically, the details are more complicated than it might appear. When typesetting numbers, there's a feature called "tabular figures" that uses alternative glyphs to make everything line up in columns. This applies to proportion fonts even if the "normal" numerals aren't the same width (or the same size), and can be extended to include number-related glyphs that are likely to appear in tabular layouts, such as making things like "12345", "(234)", "-2345", "$2345", "1234%", etc. always be the same width. A similar feature makes tabular figures the same size in bold, italic, and roman scripts.
I can certainly imagine situations where emacs might want each of these options. I think that this conversation is suggesting that the mode-line mostly wants tabular figures, and I can imagine something similar in, as an example, dired buffers.
Hope that helps,
~Chad