Re: ly:add-option behaviour

[David Kastrup]

Urs Liska <address@hidden> writes:

> I'm wondering about the behaviour of ly:add-option
>
> If I have the following file:
>
> \version "2.19.47"
>
> #(ly:add-option 'humdrum-file #f "Set to the file name of a Humdrum file")
>
> #(display (ly:get-option 'humdrum-file))
>
> and invoke LilyPond with the command line option -dmy-option=my-value
>
> The display is #f or whatever I set as default value in ly:add-option.
>
> If I comment out the ly:add-option line I get the correct value
> displayed but also a warning "no such internal option: my-option".
>
> I thought I could use that line to suppress the warning and preset the
> option with a default value that it will have when the option isn't
> passed on the command line. But I have the impression that ly:add-option
> *overwrites* any value passed through the command line.
>
> What am I missing?

ly:add-option takes effect too late to be of any use except in
LilyPond's initialization phase.

-- 
David Kastrup