From 510e74fa1cda8c6491a1ba13b2d277cc72d9b943 Mon Sep 17 00:00:00 2001
From: Matthias Felleisen <matthias@ccs.neu.edu>
Date: Sat, 5 Jan 2013 14:31:45 -0500
Subject: [PATCH] added stdin and stdout as alternatives

---
 collects/2htdp/batch-io.rkt                   | 22 ++++++++++++++-----
 .../2htdp/scribblings/batch-io.scrbl          | 15 +++++++------
 2 files changed, 25 insertions(+), 12 deletions(-)

diff --git a/collects/2htdp/batch-io.rkt b/collects/2htdp/batch-io.rkt
index 1cdf88ef1f..dd81e852b0 100644
--- a/collects/2htdp/batch-io.rkt
+++ b/collects/2htdp/batch-io.rkt
@@ -2,6 +2,7 @@
 
 (require racket/function
          racket/file
+         racket/format
          racket/string
          racket/local
          (for-syntax racket/base
@@ -13,10 +14,17 @@
 ;; todo?
 ;; -- export tokenization?
 
-(define *input-devices* `((standard-in ,current-input-port)))
-(define *output-devices* `((standard-out ,current-output-port)))
+;; I am tryiing to use these lists to automate the documentation of the
+;; functions but my scribble skills are insufficient and my time is running
+;; out. 
+(module devices racket/base
+  (provide *input-devices* *output-devices*)
+  (define *input-devices*  `((stdin ,current-input-port)   (standard-in ,current-input-port)))
+  (define *output-devices* `((stdout ,current-output-port) (standard-out ,current-output-port))))
 
-;; -----------------------------------------------------------------------------
+(require (submod "." devices))
+
+;;---------------------------------------------------------------------------------------------------
 (provide simulate-file) ;; syntax (simulate-file reader string ...)
 
 (provide
@@ -185,13 +193,17 @@
 ;; effect: ensure that f is a file in current directory or report error for t
 (define (check-input-file f t)
   (define d? (assq f *input-devices*))
-  (check-arg t (or (string? f) d?) (format "string or one of: ~a" (map car *input-devices*)) "first" f)
+  (check-arg t (or (string? f) d?) (error-message (map car *input-devices*)) "first" f)
   (check-arg t (or d? (file-exists? f)) "name of file in program's folder" "first" f))
 
 ;; effect: ensure that f is a file in current directory or report error for t
 (define (check-output-file f t)
   (define d? (assq f *output-devices*))
-  (check-arg t (or (string? f) d?) (format "string or one of: ~a" (map car *output-devices*)) "first" f))
+  (check-arg t (or (string? f) d?) (error-message (map car *output-devices*)) "first" f))
+
+;; [Listof Symbol] -> String 
+(define (error-message los)
+  (string-append "string or one of: " (string-join (map ~e los) ", ")))
 
 ;; split : String [Regexp] -> [Listof String]
 ;; splits a string into a list of substrings using the given delimiter
diff --git a/collects/teachpack/2htdp/scribblings/batch-io.scrbl b/collects/teachpack/2htdp/scribblings/batch-io.scrbl
index 03f54e9bb4..caba9aa7e5 100644
--- a/collects/teachpack/2htdp/scribblings/batch-io.scrbl
+++ b/collects/teachpack/2htdp/scribblings/batch-io.scrbl
@@ -4,6 +4,7 @@
           scribble/html-properties scribble/latex-properties
           2htdp/batch-io
           "shared.rkt"
+	  (for-syntax racket)
           (for-label scheme teachpack/2htdp/batch-io))
 
 @(require scheme/runtime-path)
@@ -32,14 +33,14 @@
 
 @; -----------------------------------------------------------------------------
 
-@(define-syntax reading
-   (syntax-rules ()
-     [(_ name ctc s)
-      @defproc[(@name [f (or/c 'standard-out (and/c string? file-exists?))]) @ctc ]{
+@(define-syntax (reading stx)
+   (syntax-case stx ()
+     [(reading name ctc s)
+     #`@defproc[(@name [f (or/c 'standard-in 'stdin (and/c string? file-exists?))]) @ctc ]{
       reads the standard input device (until closed) or the content of file
       @racket[f] and produces it as @list[s].}] 
-     [(_ name ctc [x ctc2] s ...)
-      @defproc[(@name [f (or/c 'standard-out (and/c string? file-exists?))] [@x @ctc2]) @ctc ]{
+     [(reading name ctc [x ctc2] s ...)
+      #`@defproc[(@name [f (or/c 'standard-in 'stdin (and/c string? file-exists?))] [@x @ctc2]) @ctc ]{
       reads the standard input device (until closed) or the content of file
       @racket[f] and produces it as @list[s ...].}]))
 
@@ -144,7 +145,7 @@ elements.
 There is only one writer function at the moment: 
 @itemlist[
 
-@item{@defproc[(write-file [f (or/c 'standard-out string?)] [cntnt string?]) string?]{
+@item{@defproc[(write-file [f (or/c 'standard-out 'stdout string?)] [cntnt string?]) string?]{
  sends @racket[cntnt] to the standard output device or 
  turns @racket[cntnt] into the content of file @racket[f], located in the
  same folder (directory) as the program. If the write succeeds, the