Re: within \markup, how to \translate by width of another markup?

[Werner LEMBERG]

>>>> The problem at hand is stacking fixed-width single-digit and
>>>> two-digit numbers.  Single-digit numbers should be left-aligned
>>>> for various reasons:
>>>>
>>>> ```
>>>>   9
>>>>   8
>>>>   7
>>>> ```
>>>>
>>>> If there is a two-digit number, it should be right-aligned at the
>>>> right edge of the left-aligned single-digit numbers:
>>>>
>>>> ```
>>>>  10
>>>>   9
>>>>   8
>>>> ```
>>>>
>>>> My idea was to translate the two-digit number to the left by the
>>>> width of a single digit.
>>>>
>>>> Is there a solution for this with the current LilyPond markup
>>>> commands?
>>>
>>> I don't understand why you wouldn't use alignment commands for
>>> aligning numbers.
>>
>> I would like to, however, I couldn't find a proper solution.  Do
>> you know one?
>
> \markup \right-column { 10 9 8 7 6 5 4 3 2 1 }
>
> Obviously I am missing something here.

I'm working on `format-bass-figure`.  The vertical alignment of
figured bass digits is 'left-align' by default.  Let's assume that all
digits have the same width but there is kerning between them for
better appearance.  For this reason,

```
\general-align #X #CENTER
```

doesn't align correctly because of the kerning.  Contrary to LaTeX it
seems impossible to right-align stuff on the right edge of
left-aligned stuff because LilyPond doesn't provide an equivalent to
`\hss` (which is a stretchable space).

Currently, `format-bass-figure` uses

```
\translate-scaled-markup #'(-0.7 0) ...
```

where '-0.7' is an ad-hoc value.  I would like to do

```
\translate-scaled-markup-from #X #LEFT { \number "1" } ...
```

instead to avoid the ad-hoc value.


    Werner