Making LilyPond stems disappear

Setting Stem #'stencil = ##f can cause problems. Setting Stem #'length = #0 works better.

   \new Staff {
      \override Stem #'length = #0
      c'4  d'4  e'4  f'4
      g'4  a'4  b'4  c''4
      d''4 e''4 f''4 g''4
   }

But even zero-length stems extend to the center line. The no-stem-extend attribute in stem-interface helps.

   \new Staff {
      \override Stem #'length = #0
      \override Stem #'no-stem-extend = ##t
      c'4  d'4  e'4  f'4
      g'4  a'4  b'4  c''4
      d''4 e''4 f''4 g''4
   }

Zero-length stems now exhibit true zero length.