columns in markup-command

[Kevin Patrick Barry]

Dear lilypond users,

I am trying to make a lilypond command for Roman numerals with a length property that I can override.  I have no idea what I'm doing when it comes to scheme, and I can't seem to get a column to work properly.  The function I am trying to write is below.  The problem is that the second #:line is placed outside the column after it, instead of within it.  My various attempts to force it into the column all meet with errors.  I tried using the make-column-markup function as well to no avail.  I can do it correctly using ordinary markup commands, but then I can't seem to introduce the property I want to be able to modify without causing errors. Any help would be appreciated.

Kevin

#(define-markup-command (extender layout props) ()

#:properties ((xLength 4))

(interpret-markup layout props

(markup #:concat

("V" #:super #:column (#:line (#:number #:fontsize -2 "6"

#:raise 0.5 #:draw-line (cons xLength 0)

#:number #:fontsize -2 "5"))

(#:line (#:number #:fontsize -2 "4"

#:raise 0.5 #:draw-line (cons xLength 0)

#:number #:fontsize -2 "3"))))))

\relative c' {

c1_\markup { \extender }

}