Re: Syntax change proposal:

[Trevor Daniels]

David Kastrup wrote Thursday, July 26, 2012 11:12 AM


> "Trevor Daniels" <address@hidden> writes:
> 
>> David Kastrup wrote Thursday, July 26, 2012 10:01 AM
>>
>>
>>> Keith OHara <address@hidden> writes:
>>> 
>>>> If I make a function 
>>>>   \dichrom3D { c4 d e f } 3.7
>>>> that engraves a passage so that the notes appear to float 3.7 staff-spaces
>>>> above the paper when viewed with red/cyan 3D glasses, 
>>>>
>>>> then if I use it on an isolated note \dichrom3D e 2.9
>>>> I get a dotted-half-note e floating 9.0 staff-spaces above the page.
>>
>> I'm not sure I've followed all this discussion, but if it is or
>> becomes possible to write a music function like \dichrom3D
>> which /silently/ behaves differently if one of its real arguments
>> happens to begin with a sequence that can be interpreted as
>> a duration, then we've definitely gone astray.
>>
>> Please tell me I've misunderstood something.
> 
> The _function_ does not behave differently.  It is just that more
> material belongs to the music expression argument.

That's splitting hairs.  As far as the user is concerned
\dichrom3D e 3.1 and \dichrom3D e 2.9 would behave
very differently, unless I'm still missing something.

I don't relish writing user documentation to explain
this behaviour:
Warning: if a music function takes music and a real as
two arguments and the first argument does not have an
explicit duration the second argument must not begin
with 1, 2, 4, 8, ... or the result will surprise you.

In the past you've always been in favour of eliminating
surprises.  Are you really proposing we should 
implement this syntax?

Trevor