Re: Unbound variable: \markup

[David Kastrup]

Lukas-Fabian Moser <address@hidden> writes:

> Hi Freeman,
>
> Am 04.05.20 um 16:02 schrieb Freeman Gilmore:
>> The first one below works fine but the second does not work when the
>> dollar is replaced with \markup \vcenter \huge \bold "$".   Please
>> explain why?    Why is \markup bound in the first and not in the
>> second.    I see \markup used in many places like to the second
>> example that works, what is the difference?
>
> The # in \override Accidental.before-line-breaking = #... enters
> Scheme-mode, so to speak. You may reference LilyPond variables (your 
> first version), but \markup ... is LilyPond syntax which cannot be
> used in Scheme mode. (Rule of thumb: No \anything inside of #...)
>
> (You see the difference even in the way you reference your dollar
> variable: In LilyPond mode, you'd have to write \dollar, but in Scheme 
> mode, it's just dollar.)
>
> Solution: Either construct your markup in Scheme mode, or use the
> wonderful #{ #} way of switching back to LilyPond mode. I'm not sure
> if the latter is available in 2.18.2 (which should be considered
> outdated by now!), since I lost track of when which syntax
> simplification was added (probably by David K.),

I may be mistaken, but I think it was the comparatively vaguely
described and actually rather small commit

commit d8ee829c73452cc35ef17c6c22abf5b47c754c15
Author: David Kastrup <address@hidden>
Date:   Sat Aug 27 22:23:44 2011 +0200

    Make #{ #} accept everything an assignment accepts.
    This also makes #{ #} return a void music event, and does not create
    sequential music if not necessary.

which would correspond to version 2.15.9 .  So it's comparatively old
news.

> but you can try:
>
> (ly:grob-set-property! grob 'text #{ \markup \vcenter \huge
> \with-color #darkgreen \bold "$" #})
>
> If it doesn't work, or if you insist on writing everything in Scheme,
> you can find out what to write by using your dollar variable
>
> dollar = \markup \vcenter \huge \bold "$"
>
> and asking LilyPond what it looks like in Scheme:
>
> #(display-scheme-music dollar)
>
> which displays
>
> (markup #:vcenter (#:huge (#:bold "$")))
>
> Hence, you may write
>
> (ly:grob-set-property! grob 'text (markup #:vcenter (#:huge (#:bold "$"))))

Personally, I'd just recommend to go with #{ ... #} here.

-- 
David Kastrup