Clarifying otave check (\octave) in Section 6.2.2

[Charles Cave]

I am exploring the use of the feature described in section 6.2.2 of
checking that the notes are in the correct octave.

The manual says:

Octave checks make octave errors easier to correct: a note may be followed by 
=quotes which
indicates what its absolute octave should be. In the following example,
\relative c’’ { c=’’ b=’ d,=’’ }
the d will generate a warning, because a d'' is expected (because b' to d'' is 
only a third), but
a d' is found. In the output, the octave is corrected to be a d'' and the next 
note is calculated
relative to d'' instead of d'.

Question

Specifing ' is fine for octaves above middle C, but specifying , for octave 
below doesnt work.

Here is a test program:

\version "2.8.3"


\score {
    \new Staff << 
    \relative c''' {
       c b a g f e d
      % should now have reached the C above middle C
      
      c='' b a g f e d
      % should now have reached Middle C
      c=' b a g f e d
      % should now have reached the C below Middle C

      % Problem....how can I check if the next c is
      % The C one octave below middle C?
      
      c= b a g f e d

      c=, b a g f e d     % this doesnt work 

    }
    >>
    \layout { }
}


Error:

octavecheck.ly:20:6: warning: octave check failed; expected c', found: c,
      
      c=, b a g f e d












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Charles Cave
Sydney, NSW, Australia
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