Re: ly:add-option behaviour

[Urs Liska]

Am 08.08.2016 um 16:30 schrieb David Kastrup:

That means ly:add-option is of no use in user files?

I don't really think so.  If you process several user files on the
command line, earlier files can likely define options that later files
can then use.  But that does not seem overly useful.

Indeed.

And if you add an option with ly:add-option, you may set it later with
ly:set-option.  But why use the option interface at all then?

What I would like to use the option interface for is the following (although I have just discarded the use-case at hand that triggered the message):

Write code in the files that depends on options used as configuration switches. For example ScholarLY applies coloring when a certain option is set (in openLilyLib's option handling interface). Right now the user has to configure that *in* the files (usually by commenting a line). But it would be a good thing to have such options be set on the command line because that would enable editors (like Frescobaldi) to provide user interfaces for that without having to rewrite the actual files.

Urs