Bug in lilypond-book latex output?

[Lars Kellogg-Stedman]

Hello,

While fiddling with lilypond-book (from lilypond version 2.2.1), I
took a look at the generated code that replaces the \lilypond{}
fragment in my LaTeX document.  It looks like this:

  {\parindent 0pt
  address@hidden
  \ifx\preLilyPondExample\preLilyPondExample\fi
  \def\lilypondbook{}
  \input lily-161076161.tex
  \ifx\preLilyPondExample\postLilyPondExample\fi
  address@hidden

I'm wondering if there isn't a problem in the handling of
\postLilyPondExample.  I'm not familiar with TeX beyond the basics of
LaTeX, but I'm assuming that \ifx tests if the following symbol is
executable...so the second test:

  \ifx\preLilyPondExample\postLilyPondExample\fi

Is checking the wrong symbol, and would result in an error if someone
defined \preLilyPondExample but did not define \postLilyPondExample.

-- Lars