Re: \pushToTag and \appendToTag help

[David Kastrup]

Mark Knoop <address@hidden> writes:

> At 11:48 on 13 Apr 2018, David Kastrup wrote:
>>Gianmaria Lari <address@hidden> writes:
>>> I simply don't understand it. I don't understand it because: it is
>>> too long, there are too many things, I don't understand the example
>>> goal, and I don't understand the explication following the code.  
>>
>>It adds material at two points to \test: in the inner parallel music,
>>and the outer sequential music.  The first version adds successively
>>g', e', and c' at the front of those expression, the second at the end
>>of those expressions.
>>
>>Ok, it is probably trying to show to much at once.  What's the scope
>>that you think you could deal with?  Two separate examples for
>>sequential and parallel music (probably not a good idea to work on
>>multiple tags here)?  Not adding more than a single term?
>
> I remember studying this section of documentation and having to try
> several things before understanding how these commands work. I
> probably should have made a patch at the time... Probably a simpler 
> example would be more helpful, perhaps something like:
>
> melody = { c' \tag #'append { d' } \tag #'push <f'>2 }
>
> {
>   \melody
>   \pushToTag #'push e'2 \melody
>   \appendToTag #'append e'2 \melody
> }
>
> Perhaps I'm wrong, but it's my understanding that \pushToTag requires 
> that the tagged expression is simultaneous music (enclosed within <>),
> and that \appendToTag requires that the tagged expression is 
> sequential music (enclosed within {}).

No.  Either can be either.

> Or, at least, if in the above example, melody is defined as:
>
> melody = { c' \tag #'append d' \tag #'push f'2 }
>
> then it doesn't work.

The documentation is explicit that you need a kind of music expression
making use of the "elements" field.  Sequential music and simultaneous
music are explicitly listed, chords work (assuming you only add chord
constituents), volta repeats would somewhat obscurely work (you add
alternatives).

-- 
David Kastrup