Re: negative values for \hspace don't work anymore

[David Kastrup]

Keith OHara <address@hidden> writes:

> Eluze <eluzew <at> gmail.com> writes:
>
>> with negative values for \hspace
>> 
>> since 2.15.7 this has no effect!
>> 
>> I couldn't find why this change happened or where it is documented.
>
> It changed as part of the fix for this bug
>   http://code.google.com/p/lilypond/issues/detail?id=732
>
> Does the documentation say \hspace should work with negative values?
>
> One can reverse the change, but possibly re-introduce issue 732, with :
>
> scm/markup.scm
> @@ -72,3 +72,3 @@ Example:
>                   (head (car stencils))
> -                 (xoff (+ space (interval-length (ly:stencil-extent head 
> X)))))
> +                 (xoff (+ space (interval-end (ly:stencil-extent head X)))))
>              (ly:stencil-add head

Can you?  I fail to get something like

\markup { x x x \hspace #-15 x x x }

to work, and actually this looks like a bottomless pit: on stencil
extents, interval-empty? is getting called a lot, including
the builtin ly:stencil-empty?, and those return true for stencils with a
right edge before the left edge.

It would appear that a whole lot is terribly broken with regard to
backspacing constructs as they are all being diagnosed as empty.

-- 
David Kastrup