better start-doc implementation, including alphabetizing list

svn: r7710

original commit: c4d2882557286b4c79c5f88d7918f7fc233ad1ec

collects/scribble/base-render.ss

@@ -34,14 +34,6 @@
                (substring s 0 (sub1 (string-length s))))
              sep)))
 
-      (define/public (strip-aux content)
-        (cond
-         [(null? content) null]
-         [(aux-element? (car content))
-          (strip-aux (cdr content))]
-         [else (cons (car content)
-                     (strip-aux (cdr content)))]))
-
       ;; ----------------------------------------
       ;; marshal info
 

collects/scribble/html-render.ss

@@ -63,7 +63,6 @@
                install-file
                get-dest-directory
                format-number
-               strip-aux
                quiet-table-of-contents)
 
       (define/override (get-suffix) #".html")

collects/scribble/struct.ss

@@ -270,7 +270,8 @@
   ;; ----------------------------------------
 
   (provide content->string
-           element->string)
+           element->string
+           strip-aux)
 
   (define content->string
     (case-lambda
@@ -297,12 +298,26 @@
                [else (format "~s" c)])])]
      [(c renderer sec ri)
       (cond
+       [(and (link-element? c)
+             (null? (element-content c)))
+        (let ([dest (resolve-get sec ri (link-element-tag c))])
+          (if dest
+              (content->string (strip-aux (cadr dest)) renderer sec ri)
+              "???"))]
        [(element? c) (content->string (element-content c) renderer sec ri)]
        [(delayed-element? c) 
         (content->string (delayed-element-content c ri)
                          renderer sec ri)]
        [else (element->string c)])]))
 
+  (define (strip-aux content)
+    (cond
+     [(null? content) null]
+     [(aux-element? (car content))
+      (strip-aux (cdr content))]
+     [else (cons (car content)
+                 (strip-aux (cdr content)))]))
+
   ;; ----------------------------------------
   
   (provide flow-element-width

collects/scribblings/scribble/struct.scrbl

@@ -453,7 +453,7 @@ A placeholder for a tag to be generated during the @scheme{collect
 
 
 @defproc*[([(content->string (content list?)) string?]
-           [(content->string (content list?) (p part?) (info resolve-info?)) string?])]{
+           [(content->string (content list?) (renderer any/c) (p part?) (info resolve-info?)) string?])]{
 
 Converts a list of elements to a single string (essentially
 rendering the content as ``plain text'').
@@ -465,7 +465,7 @@ element (if it has not been forced already).}
 
 
 @defproc*[([(element->string (element any/c)) string?]
-           [(element->string (element any/c) (p part?) (info resolve-info?)) string?])]{
+           [(element->string (element any/c) (renderer any/c) (p part?) (info resolve-info?)) string?])]{
 
 Like @scheme[content->string], but for a single element.
 }