Re: Why no numbers allowed in variables?

[David Kastrup]

Kieren MacMillan <address@hidden> writes:

> Hi David,
>
>> It's easy to tell the developers "make it so".  But before you can tell
>> a compiler to "make it so", you need to have a logically coherent
>> proposal.
>
> I wasn’t trying to tell anybody to "make it so" — I was just avoiding
> offering my limited (and almost certainly flawed) understanding of
> Lily’s underpinnings when others (such as yourself) might give a
> detailed, useful, and accurate answer instead.
>
> However, I’m always happy to have a discussion towards a logically
> coherent proposal that would allow a compiler to "make it so" for some
> given feature/request such as this one.
>
> So here are my first offerings:
>
>> Is c4 a note or a variable name?
>
> If I saw
>
>    c4 = something
>
> then I would think it’s a variable. If I saw
>
>   c4 something
>
> (i.e., without an assignment operator) I would think it’s a note. Is
> that a rule that can be made logically coherent for a compiler?

No.  You'd probably also think that

{ c = -3 }

is an assignment.  It isn't.  It is a note c with a relative octave
check and a fingering of 3 .  I am not enthusiastic about all of the
inherited design decisions but there are a lot of scores and score
writers relying on them.

>>  Is \part2 the variable "part" followed
>> by a half note, or is it the variable "part2"?
>
> If I were developing Lilypond code, I simply wouldn’t allow a note
> value to be post-fixed to a variable, so
>
>    \part2

It isn't "post-fixed".  It is a note of its own.

partI = { tambourine 4. 8 4 4 }

\drums { \rhythm 2 r2 }

is valid LilyPond input.

> would have only one interpretation (i.e., as the variable
> "part2"). But that’s only because I can’t see a good use case for the
> alternative. Can anyone suggest a reason to allow
>
>    part = { c4 8 8 }
>    \part2
>
> where the latter is intended to do something… um… coherent?

See above.

-- 
David Kastrup