Re: Bar lines

[David Kastrup]

Marc Hohl <address@hidden> writes:

> Am 07.03.2013 10:06, schrieb David Kastrup:
>> [...]
>> Ok, here is the deal: I promise to give real thought about a way to
>> _define_ repeat structures in such a straightforward manner that a user
>> would understand how to create repeat structures of his own including
>> working Midi and \expandRepeats as long as he can hack together the
>> glyphs for the _looks_.
>>
>> And you promise think about how the barline definition interface might
>> be made more friendly when in-line recipe and call string are not forced
>> to be the same, and how more complex recipes might benefit from not
>> being string-only.  I can also imagine recipes/definitions like
>>
>> (define-bar-type "|:"
>>    ".|:" :prebreak "|" :postbreak ".|:" :spanbar ("xxx" "yyy"))
> Ok, sounds like a good deal ;-)
>
> What exactly do you mean by :spanbar ("xxx" "yyy")?

I have absolutely no idea.  I was just throwing out possible Scheme
syntax elements that could be used in such an interface, probably based
on define*-public (which parses keywords argument like above).

("xxx" "yyy") without quoting the list is likely a bad idea since it
would require define-bar-type to be a macro, and that's probably
uncalled for.  But probably keyword arguments with single strings will
work well enough.

> As Janek pointed out some months ago, he wanted to be able
> to define separate span-bar types on-the-fly, so we probably
> should end up with something like
>
> (define-bar-type "|:"
>    ".|:" :prebreak "|" :postbreak ".|:"
>    :spanbar ".|" :spanbar-prebreak "|" :spanbar-postbreak ".|")
>
> ?

Looks reasonable.  The keyword arguments are a mouthful to type, but I
think they make things quite more readable.

-- 
David Kastrup