use a counter to get separate tags and section titles

svn: r13653

original commit: 9d06dd7f579015518ed07994c2c733a3bc74d8bc

collects/games/chat-noir/literate-doc-wrapper.ss

@@ -3,16 +3,30 @@
 ;; Use this module to create literate doc wrappers -- files that require the
 ;; literate code in a way that makes it a scribble file.
 
-(provide include chunk
-         (all-from-out scribble/manual))
+(provide include chunk (all-from-out scribble/manual))
 
-(require scribble/manual scribble/decode scheme/include)
+(require scribble/manual scribble/decode scheme/include
+         (for-syntax scheme/base syntax/boundmap))
+
+(begin-for-syntax
+  ;; maps chunk identifiers to a counter, so we can distinguish multiple uses
+  ;; of the same name
+  (define chunk-number (make-free-identifier-mapping)))
 
 ;; define `chunk' as a macro that typesets the code
-(define-syntax-rule (chunk name expr ...)
-  (make-splice (list (subsection #:tag (format "~a" 'name)
-                                 (scheme name))
-                     (schemeblock expr ...))))
+(define-syntax (chunk stx)
+  (syntax-case stx ()
+    [(_ name expr ...)
+     (let ([n (add1 (free-identifier-mapping-get
+                     chunk-number #'name (lambda () 0)))])
+       (free-identifier-mapping-put! chunk-number #'name n)
+       (with-syntax ([tag (format "~a~a" (syntax->datum #'name)
+                                  (if (n . > . 1) (format ":~a" n) ""))]
+                     [(more ...) (if (n . > . 1)
+                                   #`((subscript #,(format "~a" n)))
+                                   #`())])
+         #'(make-splice (list (subsection #:tag tag (scheme name) more ...)
+                              (schemeblock expr ...)))))]))
 
 ;; HACK: provide a fake `module', which makes it possible to include a module
 ;; and get only its code in.