+(define-markup-command (overlay layout props args)
+ (markup-list?)
+ #:category align
+ "
+@cindex merging text
+
+Takes a list of markups combining them.
+
+@lilypond[verbatim,quote]
+\\markup {
+ \\fontsize #5
+ \\override #'(thickness . 2)
+ \\overlay {
+ \\draw-line #'(0 . 4)
+ \\arrow-head #Y #DOWN ##f
+ \\translate #'(0 . 4)\\arrow-head #Y #UP ##f
+ }
+}
+@end lilypond"
+ (apply ly:stencil-add (interpret-markup-list layout props args)))
+