Extra note in lilypond mensural layout with petrucci-f4

Question

I'm trying to set some 16th century music. The mensural style overrides do a pretty good job of matching the original notation, but an extra c' appears at the beginning of the staff when I call \clef petrucci-f4.

How can I get the clef glyph I want without the extra note appearing?

Here's a simple example:

\version "2.18.2"

{
  \override NoteHead.style = #'petrucci
  \override Staff.TimeSignature.style = #'mensural
  \clef petrucci-f4
  \cadenzaOn
  g,1 g
}

Note there are only the two G notes in the input.

Answer 1

petrucci-f4 is not a "word" according to LilyPond syntax. so your input is equivalent to

\clef "petrucci-f"    4

In version 2.18, the 4 will trigger a syntax error. In version 2.19 (well, for most of 2.19.x), the 4 is an extra quarter note with the pitch of the preceding note. Since there is no preceding note in that score, more or less a default c' will be taken.

So it would be my guess that you are not using LilyPond version 2.18.2 (as declared in the file) but some 2.19.x version, and you are getting the specified result.

The obvious solution also mentioned in another answer is to put all of petrucci-f4 in double quote marks, turning it into a single "word".

Answer 2

There is something wrong with the example in your OP. When I copy and paste it, I get the error message

test.ly:6:19: error: syntax error, unexpected UNSIGNED
  \clef petrucci-f
                  4

On the other hand

\clef "petrucci-f4"

works correctly for me, and doesn't give the extra note.

I suspect that your original Lilypond input is different from what you posted, and the f4 was somehow being interpreted as a quarter-note, not as part of the clef specification.