Curiousity question about explicitClefVisibility

[Jim Long]

I just stubbed my toe on something silly, and I don't understand
why it is the way it is.

Why does this work:

\version "2.16.0"

\score {
  \relative c' {
    c4 c c c
    \break
    \set Staff.explicitClefVisibility = #end-of-line-invisible
    \clef bass
    c4 c c c
    \unset Staff.explicitClefVisibility
    \break
  }
}


But this doesn't:

\version "2.16.0"

\score {
  \relative c' {
    c4 c c c
    \break
    \set Staff.explicitClefVisibility = #end-of-line-invisible
    \clef bass
    \unset Staff.explicitClefVisibility
    c4 c c c
    \break
  }
}

I couldn't immediately think of why there has to be music between the
\clef and the \unset in order for the #end-of-line-invisible to take
effect.


Thank you!

Jim