doubleSlurs

[David Bobroff]

In this example everything is fine except that I don't get a double
slur.  I want a slur from the f across the barline to the ges.  Am I
committing a user error or is this a bug?  I've tried the contexts
Voice, Staff, and Score with the same result from each.

-David

\paper{
    linewidth = 7\cm
}

\score { 
    
    \context Staff \relative c {  
        \set doubleSlurs = ##t
        \clef F
        <<
            {
                
                \stemDown
                <<
                    {des'1 ~ des2. ~ des8 r} \\ {<bes ges>2_\( <f des>-( <ges 
des>2.-)
~  <ges des>8\) r}  
                >>
                
            }
            
        >>
    }
}