\version "2.19.81"

global = {
  \key c \major
  \time 4/4
  \partial 2
}

violin = \relative c'' {
  \global
  \override Score.BarNumber.break-visibility = ##(#t #t #t)
  \set Score.alternativeNumberingStyle = #'numbers-with-letters
  \repeat volta 2 {
    c2 | % two-beat anacrusis
    c4 d e f |
  }
  \alternative {
    {
      g2
    }
    {
      g4 g,
    }
  }
  \repeat volta 2
  {
    \partial 2
    %\override Score.BarNumber.break-visibility = ##(#f #f #f)
    c2 | % should be a continuation of the previous measure number
    %\override Score.BarNumber.break-visibility = ##(#t #t #t)
    %\set Score.currentBarNumber = #3
    c1 |
    c2
  }
}

\score {
  \new Staff \violin
  \layout { }
}