From eb4e22904a73410bbcd0ddf52f3287a08f952d86 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Sun, 19 Jan 2014 15:22:15 -0800
Subject: [PATCH] scribble: `++args` for passing command-line arguments to
 documents

original commit: 392ea2e91d6c51157daa35dd1aa72cca951b6ac9
---
 .../scribblings/scribble/running.scrbl        | 19 ++++++++++++++++++
 .../scribble-lib/scribble/run.rkt             | 20 ++++++++++++-------
 2 files changed, 32 insertions(+), 7 deletions(-)

diff --git a/pkgs/scribble-pkgs/scribble-doc/scribblings/scribble/running.scrbl b/pkgs/scribble-pkgs/scribble-doc/scribblings/scribble/running.scrbl
index 8f31300c..cbe17bdf 100644
--- a/pkgs/scribble-pkgs/scribble-doc/scribblings/scribble/running.scrbl
+++ b/pkgs/scribble-pkgs/scribble-doc/scribblings/scribble/running.scrbl
@@ -164,3 +164,22 @@ in @filepath{a.scrbl} and @filepath{b.scrbl}, then
 builds @filepath{c.html} with cross-reference links into
 @filepath{a.html} and @filepath{b.html}.
 
+
+@section{Passing Command-Line Arguments to Documents}
+
+When @exec{scribble} loads and renders a document module, by default
+it sets @racket[current-command-line-arguments] to an empty vector.
+Use the @DPFlag{arg} flag (any number of times) to add a string to
+@racket[current-command-line-arguments].
+
+For example,
+
+@commandline{scribble ++arg --mode ++arg fast turtle.scrbl}
+
+causes @racket[(current-command-line-arguments)] to return
+@racket['#("--mode" "fast")] while @filepath{turtle.scrbl} is loaded
+and rendered, which could affect the content that
+@filepath{turtle.scrbl} generates if it uses
+@racket[current-command-line-arguments].
+
+@history[#:changed "1.1" @elem{Added the empty-vector default and @DPFlag{arg} flag.}]
\ No newline at end of file
diff --git a/pkgs/scribble-pkgs/scribble-lib/scribble/run.rkt b/pkgs/scribble-pkgs/scribble-lib/scribble/run.rkt
index 7a6930bf..8bda9927 100644
--- a/pkgs/scribble-pkgs/scribble-lib/scribble/run.rkt
+++ b/pkgs/scribble-pkgs/scribble-lib/scribble/run.rkt
@@ -30,6 +30,7 @@
 (define current-directory-depth    (make-parameter 0))
 (define current-quiet              (make-parameter #f))
 (define helper-file-prefix         (make-parameter #f))
+(define doc-command-line-arguments (make-parameter null))
 
 (define (read-one str)
   (let ([i (open-input-string str)])
@@ -119,18 +120,23 @@
    [("++info-in") file "load format-specific cross-ref info from <file>"
     (current-info-input-files
      (cons file (current-info-input-files)))]
+   [("++arg") arg "add <arg> to current-command-line-arguments"
+    (doc-command-line-arguments
+     (cons arg (doc-command-line-arguments)))]
    #:once-each
    [("--quiet") "suppress output-file and undefined-tag reporting"
     (current-quiet #t)]
    #:args (file . another-file)
    (let ([files (cons file another-file)])
-     (build-docs (map (lambda (file) 
-                        ;; Try `doc' submodule, first:
-                        (if (module-declared? `(submod (file ,file) doc) #t)
-                            (dynamic-require `(submod (file ,file) doc) 'doc)
-                            (dynamic-require `(file ,file) 'doc)))
-                      files)
-                 files))))
+     (parameterize ([current-command-line-arguments
+                     (list->vector (reverse (doc-command-line-arguments)))])
+       (build-docs (map (lambda (file) 
+                          ;; Try `doc' submodule, first:
+                          (if (module-declared? `(submod (file ,file) doc) #t)
+                              (dynamic-require `(submod (file ,file) doc) 'doc)
+                              (dynamic-require `(file ,file) 'doc)))
+                        files)
+                   files)))))
 
 (define (build-docs docs files)
   (when (and (current-dest-name)