Re: inherit-acceptability

[David Kastrup]

Timothy Lanfear <address@hidden> writes:

> I like, and am using, the new inherit-acceptability feature. Without
> thinking too much about what I was doing, I put inherit-acceptability
> inside the definition of a new context, instead of following as shown
> in the documentation.
>
> \layout {
>   \context {
>      \StaffGroup
>      \name "RecorderConsort"
>      \alias StaffGroup
>      \inherit-acceptability RecorderConsort StaffGroup
>   }
> }
>
> It works fine.

That's like saying calling a void function performing a global
assignment inside of a music expression works fine.  In some manner it
does, but it bears no relation whatsoever to its placement inside of the
music expression.

It's more of a weird quirk than anything else and should be avoided.

> Would inherit-acceptability ever be used other than right away when
> defining a new context?

If the desired _end_ result of acceptabilities is not equality, you
might use them in an order not necessarily matching the definition
order.

> And if not, the first argument is redundant; perhaps it can be
> inferred?

It can't.  A context definition is a purely syntactical entity: it has
no scopes or other tangible features associated with it.  A void
function is only permitted here for the sake of making it possible to
write a function that conditionally returns a context mod, like

#(if [condition] #{ \with { \consists "Bar_default_engraver" } #})

which will be silently accepted (and ignored) when [condition] is false.

The return value of \inherit-acceptability is indistinguishable from
that, but the environment in which it is called is indistinguishable
from the enclosing output definition.

-- 
David Kastrup