Re: Issue 5301: Refactor mark events ... (issue 340650043 by address@hidden)

[nine . fierce . ballads]

https://codereview.appspot.com/340650043/diff/1/ly/music-functions-init.ly
File ly/music-functions-init.ly (right):

https://codereview.appspot.com/340650043/diff/1/ly/music-functions-init.ly#newcode833
ly/music-functions-init.ly:833: #(define-music-function (label)
((integer-or-markup?))
Alternatively, one could blame the mark formatter (or whatever it is)
for failing gracelessly given a value that satisfies the predicate; but
if nobody cares to argue that negative mark numbers might be valuable to
somebody, I am willing to use index? in this patch.

Using index? would still require the formatters to handle zero
gracefully.  That seems reasonable to me, but if there are other
opinions, please express them.  Either way, I do not want to revamp the
formatters now.

David makes a good point that "if exactness is required for indexing, we
should fold it into the index? predicate," but I don't want to devote
time to investigating his predicate, and I don't want to risk side
effects by mixing such a change into my patch without investigation.

https://codereview.appspot.com/340650043/