Re: simplify previous patch-set by special casing 2-line staves (issue 6506090)

[Benkő Pál]

>> "dots in outer spaces" was inspired by your comment
>> http://codereview.appspot.com/6488097#msg7
>
> I was talking about a tab staff with larger staff-space, but with just
> two staff-positions for each line.
>
> Anyone writing #'line-positions = #'(-10 -2 6 14) would be planning to
> put a lot of pitches in those eight staff-positions between the middle
> lines, and will be surprised that LilyPond considers that not enough
> room for repeat dots.
>
> More likely, someone might have removed the center line from a 5-line
> staff
>   #'line-positions = #'(-4 -2 2 4)
> for some unusual instrument, and will not like the change.
>
> But, if anyone complains, we can insert 0 into 'folded-staff
>
>
>> (are there chromatic or microtonal notations where these steps are
>> smaller than a third?)
>
> seems crazy to me, but people do it,
> <http://musicnotation.org/software/lilypondusers.html>
>
>
>> I think this
>> simplification is oversimplification as it cannot distinguish
>>
>> \override #'line-count = #2
>>
>> from
>>
>> \override #'line-count = #2
>> \override #'staff-space = #2
>
> Why do you want to distinguish these two cases?

because (maybe depending on set-global-staff-size and
layout-set-staff-size) the latter has enough room for two
dots, the former hasn't.  and that brings me back to my
main argument: I can't guess why the user chose a
specific way of manipulating the staff and how (s)he
interprets it, I also don't know at that point why the staff
space is that big as is (staff-size, set-global-staff-size,
layout-set-staff-size), but I know exactly whether one
or two dots have enough room or not.

I admit that the request to restore the look of the original
repeat sign of a TabStaff makes all that not enough.

I also think that users would be surprised that

\override #'staff-space = #0.5

and

\override #'line-positions = #'(-2 -1 0 1 2)

makes the repeat sign look different, even if they know that
pitches are at different places - but who thinks that the dots
of a repeat sign mark pitches?

p