>> I asked this question some time ago, and David Kastrup was kind enough
>> to put me right.
>> The problem , as you mentioned, is in the way that numbers are used
>> for durations. Consider the following code:
>> chord = <c e g>
>> chord2= <d f a>
>> c1 \chord2
>> Should the second element be interpreted as <c e g>2 or <d f a>1? I
>> imagine this would confuse the lexer horribly.
> The lexer follows rules. It's never confused. The user is something
> different. Incidentally, chords cannot be resized, so \chord2 would be
> interpreted as
> <c e g> <c e g>2
> due to how isolated durations in music are interpreted.
>> No doubt some rules could be written to resolve this, but it would
>> need some recoding.
> Durations generally don't require space separation, like with a4 and so
> on. Balancing conflicting desires and requirements and consistency is
> always tricky. TeX has also chosen not to admit numbers into
> identifiers and people tend to complain it cramps their style.