referencing hash key with music symbol

[Jeffery Shivers]

Hi LP team,

I am working on automating editorial commands with ScholarLY, and I am
having some trouble pulling a music function that is stored in a hash
table. If I make a table and assign a key 'Slur to slurDashed, I can use it
successfully in the following example:

#(define mytable (make-hash-table))

#(hash-set! mytable 'Slur slurDashed)


\score {

    \new Staff {

        #(let ((func (hash-ref mytable 'Slur)))

            #{

                #func f'( g')

            #})

    }

}


In that context, "Slur" is of course an arbitrary name. However, when a
symbol is used to indicate what item is being annotated in scholarly, e.g.:


\criticalRemark \with {

    message = "my message"

    apply = addition

} Slur f'( g') % <<<< "Slur" indicated here


... we will use that symbol to determine what function, previously assigned
to the so-named key in the hash table, to apply to the music. However, when
I attempt to do this, Lily (or maybe Guile) doesn't cooperate. I don't have
a very useful way of minimizing this process, since it takes place in one
of the larger chunks of the library's code, but basically `item` is the
argument that the symbol satisfies, and in (sort of) context, the
unsuccessful use of it looks like:


... (let ((func (hash-ref mytable item))) ...


Replacing "item" with 'Slur works like a charm - `func` applies a dashed
slur in a lilypond code block in the local scope. But I can't seem to work
out why using the symbol name doesn't also work.


Hopefully I've explained the issue clearly enough, and I apologize for the
lack of a better non-working example. Any help is very much appreciated.


Best,

Jeffery