From 5296a0a877ffc7b796471ab4ddc6585e3d819fd4 Mon Sep 17 00:00:00 2001
From: Matthias Felleisen <matthias@racket-lang.org>
Date: Wed, 30 Dec 2009 22:45:12 +0000
Subject: [PATCH] added gensym, current-millisecond, sleep, assoc,
 with-i/o-from-to

svn: r17444
---
 collects/lang/private/advanced-funs.ss | 90 +++++++++++++++-----------
 1 file changed, 53 insertions(+), 37 deletions(-)

diff --git a/collects/lang/private/advanced-funs.ss b/collects/lang/private/advanced-funs.ss
index fa73ebbbc0..21830fac94 100644
--- a/collects/lang/private/advanced-funs.ss
+++ b/collects/lang/private/advanced-funs.ss
@@ -1,78 +1,94 @@
 (module advanced-funs scheme/base
   (require "teachprims.ss"
-	   mzlib/etc
-	   mzlib/list
-	   mzlib/pretty
-	   syntax/docprovide
+           mzlib/etc
+           mzlib/list
+           mzlib/pretty
+           syntax/docprovide
            scheme/promise
-	   "../posn.ss"
+           "../posn.ss"
            (for-syntax scheme/base))
-
+  
   (provide-and-document
    procedures
-
+   
    ("Reading and Printing"
     (print (any -> void)
-	   "to print the argument as a value to stdout")
+           "to print the argument as a value to stdout")
     (display (any -> void)
-	     "to print the argument to stdout (without quotes on symbols and strings, etc.)")
+             "to print the argument to stdout (without quotes on symbols and strings, etc.)")
     (write (any -> void)
-	   "to print the argument to stdout (in a traditional style that is somewhere between print and display)")
+           "to print the argument to stdout (in a traditional style that is somewhere between print and display)")
     (pretty-print (any -> void)
-	   "like write, but with standard newlines and indentation")
+                  "like write, but with standard newlines and indentation")
     (printf (string any ... -> void)
-	    "to format the rest of the arguments according to the first argument and print it to stdout")
+            "to format the rest of the arguments according to the first argument and print it to stdout")
     (newline (-> void)
-	     "to print a newline to stdout")
+             "to print a newline to stdout")
     (read (-> sexp) "to read input from the user"))
    
    ("Lists"
-     (list? (any -> boolean)
-       "to determine whether some value is a list")
-
+    (list? (any -> boolean)
+           "to determine whether some value is a list")
+    
     ((advanced-list* list*) (any ... (listof any) -> (listof any)) 
-     "to construct a list by adding multiple items to a list")
-
+                            "to construct a list by adding multiple items to a list")
+    
     ((advanced-cons cons) (X (listof X) -> (listof X))
-     "to construct a list")
-
+                          "to construct a list")
+    
     ((advanced-append append) ((listof any) ... -> (listof any))
-     "to create a single list from several"))
+                              "to create a single list from several")
+    
+    (assoc 
+     (any (listof any) -> (listof any) or false)
+     "to produce the first element on the list whose first is equal? to v; otherwise it produces false"))
    
    ("Misc"
-    (random (-> (and/c real? inexact? (>/c 0) (</c 1)))
-            "to generate a random number between 0 and 1 (excl).")
+    (random (-> (and/c real inexact? (>/c 0) (</c 1)))
+     "to generate a random number between 0 and 1 (excl).")
+    (gensym (-> symbol?)
+     "to generate a new symbol, different from all symbols in the program")
+    (sleep (-> positive-number void)
+     "to cause the program to sleep for the given number of seconds")
+    (current-milliseconds (-> exact-integer)
+     "to return the current “time” in fixnum milliseconds (possibly negative)")
+    
+    (with-input-from-file (string (-> any) -> any)
+      "to open the given string as an input file and to make it the current input port")
+    (with-output-to-file (string (-> any) -> any)
+      "to open the given string as an output file and to make it the current output port")
+    
     (force (delay -> any) "to find the delayed value; see also delay")
     (promise? (any -> boolean) "to determine if a value is delayed")
     (void (-> void) "produces a void value")
     (void? (any -> boolean) "to determine if a value is void"))
-
+   
    ("Posns"
     (set-posn-x! (posn number -> void) "to update the x component of a posn")
     (set-posn-y! (posn number -> void) "to update the x component of a posn"))
-
+   
    ("Vectors"
     (vector (X ... -> (vector X ...))
-	    "to construct a vector")
+            "to construct a vector")
     (make-vector (number X -> (vectorof X))
-		 "to construct a vector")
+                 "to construct a vector")
     (build-vector (nat (nat -> X)  -> (vectorof X))
-		  "to construct a vector")	
+                  "to construct a vector")	
     (vector-ref ((vector X) nat -> X)
-		"to extract an element from a vector")
+                "to extract an element from a vector")
     (vector-length ((vector X) -> nat)
-		   "to determine the length of a vector")	
+                   "to determine the length of a vector")	
     (vector-set! ((vectorof X) nat X -> void)
-		 "to update a vector")
+                 "to update a vector")
     (vector? (any -> boolean)
-	     "to determine if a value is a vector"))
-
+             "to determine if a value is a vector"))
+   
    ("Boxes"
     (box (any -> box)
-	 "to construct a box")
+         "to construct a box")
     (unbox (box -> any)
-	   "to extract the boxed value")
+           "to extract the boxed value")
     (set-box! (box any -> void)
-	      "to update a box")
+              "to update a box")
     (box? (any -> boolean)
-	  "to determine if a value is a box"))))
+          "to determine if a value is a box"))))