Footnote html numbers

scribble-doc/scriblib/scribblings/footnote.scrbl

@@ -8,10 +8,37 @@
 
 @defmodule[scriblib/footnote]
 
-@defproc[(note [pre-content pre-content?] ...) element?]{
+@defparam[note-number number (or/c integer? #f 'next)]{
+  This parameter controls the number of footnotes in the HTML renderer.
+  See @racket[note] for how it is interpreted.
+
+  To enable footnote numbers in HTML,
+  add @racket[#:number 'next] to your first call to @racket[note]
+  (you can also add it to subsequent calls, but that is not necessary);
+  or set this parameter to either 1 or @racket['next].
+  To disable footnote numbers again in HTML,
+  set this parameter back to @racket[#f] (the default).
+
+@history[#:added "1.62"]
+}
+
+@defproc[(note [#:number number (or/c integer? boolean?) (note-number)]
+               [pre-content pre-content?] ...) element?]{
 
 Creates a margin note for HTML and a footnote for Latex/PDF output.
 
+If rendering HTML, then the number parameter is used, which default to @racket[(note-number)].
+If it is @racket[#f] then no number is used (default / legacy behavior).
+If it is @racket['next] and @racket[(note-number)] is an integer,
+then the latter value is used.
+If it is @racket['next] and @racket[(note-number)] is not integer,
+then the value 1 will be used instead.
+If it is an integer, then its value is used.
+If an integer value is used, then @racket[(note-number)] is set to the next integer.
+
+@history[#:changed "1.63" @elem{Added @racket[#:number].}]
+}
+
 To produce a numbered note for HTML (which can useful if a CSS
 specialization changes how ``margin notes'' are rendered), use
 @racket[define-footnote] with @racket[#:margin], instead.

scribble-lib/info.rkt

@@ -21,7 +21,7 @@
 
 (define pkg-authors '(mflatt eli))
 
-(define version "1.62")
+(define version "1.63")
 
 (define license
   '((Apache-2.0 OR MIT)

scribble-lib/scriblib/footnote.rkt

@@ -2,6 +2,8 @@
 
 (require (for-syntax racket/base)
          scribble/core
+         (only-in scribble/base superscript)
+         (only-in scriblib/render-cond cond-element)
          scribble/decode
          scribble/html-properties
          scribble/latex-properties
@@ -11,6 +13,7 @@
          "private/counter.rkt")
 
 (provide note
+         note-number
          define-footnote)
 
 (define footnote-style-extras
@@ -24,12 +27,43 @@
 (define note-box-style (make-style "NoteBox" footnote-style-extras))
 (define note-content-style (make-style "NoteContent" footnote-style-extras))
 
-(define (note . text)
-  (make-element 
-   note-box-style
-   (make-element note-content-style
-                 (decode-content text))))
+(define note-number (make-parameter #f))
 
+;; TODO: move this utility function somewhere it can be exported from
+(define (xexpr-element xexpr)
+  (make-element (make-style #f (list (xexpr-property xexpr ""))) '()))
+
+(define (note #:number [number (note-number)] . text)
+  (define (no-number)
+    (make-element
+      note-box-style
+      (make-element note-content-style
+                    (decode-content text))))
+  (cond-element
+    [html
+      (if number
+        (let* ([n (if (integer? number)
+                    number
+                    (let ([nn (note-number)])
+                      (if (integer? nn) nn 1)))]
+               [a (lambda (x y)
+                    (xexpr-element `[a ([name ,(format "__footnote_~a_~a__" x n)]
+                                        [href ,(format "#__footnote_~a_~a__" y n)])
+                                       [sup () ,(format "~a" n)]]))])
+          (note-number (+ n 1))
+          (make-element plain
+            (list
+              (a "source" "target")
+              (make-element
+                note-box-style
+                (make-element note-content-style
+                  (list
+                    (a "target" "source")
+                    ": "
+                    (decode-content text)))))))
+        (no-number))]
+    [else
+      (no-number)]))
 
 (define footnote-style (make-style "Footnote" footnote-style-extras))
 (define footnote-ref-style (make-style "FootnoteRef" footnote-style-extras))