includeFromSong =
#(define-void-function (filename) (string?)
  (let ((noDefaultOutputBackup noDefaultOutput))
    (set! noDefaultOutput #t)
    (ly:parser-parse-string (ly:parser-clone)
      (ly:format "\\include \"~a\""
      (string-append
        (dirname (dirname (current-filename)))
        file-name-separator-string
        "lilypond-song-includes"
        file-name-separator-string
        "liedbausteine"
        file-name-separator-string
        filename)))
    (set! noDefaultOutput noDefaultOutputBackup)))