Re: stencils: let some stencils carry a box-extent; issue 3255 (issue 9295044)

[dak]

https://codereview.appspot.com/9295044/diff/51001/lily/stencil-integral.cc
File lily/stencil-integral.cc (right):

https://codereview.appspot.com/9295044/diff/51001/lily/stencil-integral.cc#newcode385
lily/stencil-integral.cc:385: Interval x_ext = robust_scm2interval
(scm_car (expr), Interval () );
Ok, you'll probably hate me for this...  But wouldn't it make sense to
allow for extents and/or extent bounds to be #f and/or #t in order to
indicate being unbounded and/or prefer the skyline?

It looks at least somewhat awkward that one can't just replace the
horizontal or vertical skyline alone with fixed extents but always has
to do it in tandem.

https://codereview.appspot.com/9295044/