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## Re: TimeSignature with note in denominator

 From: Carl Sorensen Subject: Re: TimeSignature with note in denominator Date: Sat, 13 Nov 2021 19:50:08 +0000 User-agent: Microsoft-MacOutlook/10.10.1b.201012

```I have not been a strong contributor to this thread.   And I have not been a
strong advocate for the time signatures with a notehead in the denominator.  I
think all of those time signatures can be expressed just as well as a compound
meter.

HOWEVER,

In looking at this, is seems the lexer (and the propery timeSignatureFraction)
are not semantically correct.

Although the time signature looks like a fraction, it is not.  A fraction has
numbers in the denominator and the numerator (and strictly speaking, a fraction
properly has integers in the numerator and denominator -- if they are not
integers, it's a quotient, not a fraction, IIUC).  And the time signature has
an integer in the "numerator" and a duration in the "denominator".

I'm not sure it is worth the work to get semantically correct, but
semantically, \time 4/4 should not be a fraction of two integers; it should be
a pair of a count and a duration.

And if we had semantically correct time signature entry, Kieren's wish for a
different display for the duration would be relatively straightforward,
although we would potentially have an "isoduration" problem that is analogous
to the "chord name semantics" problem -- there is no difference in duration
between 4~4 and 2, so we couldn't preserve 4~4.  Similarly, we could not tell
the difference between 8.~8 and 8~8., although I can't imagine how the
difference between these two representations would be important; both represent
a duration of 5 eighth-notes.

Anyway, like I said earlier, I'm not sure that it's worth changing the
internals since they work so well for the lilypond core functionality
(traditional western music), but I noticed the semantic error as I read this