(m (interpret-markup layout props arg)))
(bracketify-stencil m Y th (* 2.5 th) th)))
\f
-
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-;; size indications arrow
+;; Delayed markup evaluation
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+(define-builtin-markup-command (page-ref layout props label gauge default)
+ (symbol? markup? markup?)
+ "Reference to a page number. @var{label} is the label set on the referenced
+page (using the @code{\\label} command), @var{gauge} a markup used to estimate
+the maximum width of the page number, and @var{default} the value to display
+when @var{label} is not found."
+ (let* ((gauge-stencil (interpret-markup layout props gauge))
+ (x-ext (ly:stencil-extent gauge-stencil X))
+ (y-ext (ly:stencil-extent gauge-stencil Y)))
+ (ly:make-stencil
+ `(delay-stencil-evaluation
+ ,(delay (ly:stencil-expr
+ (let* ((table (ly:output-def-lookup layout 'label-page-table))
+ (label-page (and (list? table) (assoc label table)))
+ (page-number (and label-page (cdr label-page)))
+ (page-markup (if page-number (format "~a" page-number) default))
+ (page-stencil (interpret-markup layout props page-markup))
+ (gap (- (interval-length x-ext)
+ (interval-length (ly:stencil-extent page-stencil X)))))
+ (interpret-markup layout props
+ (markup #:concat (#:hspace gap page-markup)))))))
+ x-ext
+ y-ext)))