clean up from svn

collects/2htdp/universe-request.txt

@@ -0,0 +1,77 @@
+From: Robby Findler <robby@eecs.northwestern.edu>
+Date: June 16, 2009 5:16:50 PM EDT
+To: Matthias Felleisen <matthias@ccs.neu.edu>
+Subject: Fwd: Universe key handler request
+
+I was cleaning out my inbox and found this. Probably too late, but I
+thought I'd still pass it on in case you'd forgotten. 
+
+Robby
+
+Forwarded conversation
+Subject: Universe key handler request
+------------------------
+
+From: Robby Findler <robby@eecs.northwestern.edu>
+Date: Tue, Feb 24, 2009 at 9:22 AM
+To: matthias@ccs.neu.edu
+
+
+Can you make the key handlers in universe take 3 arguments instead of
+2? That is, it takes a world, a key-event and a boolean where the key
+event does not include 'release and the Boolean indicates if the key
+was pressed down or not.
+
+Robby
+
+----------
+From: Matthias Felleisen <matthias@ccs.neu.edu>
+Date: Tue, Feb 24, 2009 at 9:24 AM
+To: Robby Findler <robby@eecs.northwestern.edu>
+
+
+
+I guess. Why is this useful?
+
+
+----------
+From: Matthias Felleisen <matthias@ccs.neu.edu>
+Date: Tue, Feb 24, 2009 at 9:25 AM
+To: Robby Findler <robby@eecs.northwestern.edu>
+
+
+
+P.S. and how would you signal the release of a key?
+
+
+----------
+From: Robby Findler <robby@eecs.northwestern.edu>
+Date: Tue, Feb 24, 2009 at 9:29 AM
+To: Matthias Felleisen <matthias@ccs.neu.edu>
+
+
+the Boolean!
+
+It is useful for multiple key presses that overlap but it is also
+useful that it matches what you think when you look at a keyboard.
+
+Robby
+
+
+----------
+From: Matthias Felleisen <matthias@ccs.neu.edu>
+Date: Tue, Feb 24, 2009 at 10:19 AM
+To: Robby Findler <robby@eecs.northwestern.edu>
+
+
+
+
+Wait. Say I press a key
+
+Ê*------------------------------||-------------------------------------*
+Êkey-press Ê Êholding it down Êthe event handler is called with #t Ê more key presses, no release?
+
+when does the program find out that I have released the key?
+
+
+

collects/2htdp/universe-syntax-parse.ss

@@ -0,0 +1,117 @@
+#lang scheme/load
+
+(module auxs scheme 
+  (define (world->world> proc0)
+    (printf "a world to world function\n")
+    proc0)
+  
+  (define (positive-number> rate0)
+    (printf "a positive number")
+    rate0)
+  
+  ;; String String Syntax[id] -> Syntax 
+  (define (pre-post-name pre post name)
+    (datum->syntax 
+     name (string->symbol (string-append pre (symbol->string (syntax-e name)) post))))
+  
+  (provide (all-defined-out)))
+
+(module clauses scheme 
+  
+  (require syntax/parse (for-syntax scheme 'auxs unstable/syntax)
+           (for-template scheme/base 'auxs))
+  
+  
+  (define-syntax (define-clause stx)
+    (syntax-case stx ()
+      [(_ name (proc p-ctc) (rate r-ctc) ...)
+       (with-syntax ([name-clause (pre-post-name "" "-clause" #'name)]
+                     [(rate0 ...) (generate-temporaries #'(rate ...))])
+         (with-syntax ([((thing ...) ...) #'((#:with rate #'(r-ctc rate0)) ...)])
+           #`
+           (begin
+             (provide name name-clause)
+             
+             (define-syntax (name . x)
+               (raise-syntax-error 'name "used out of context" x))
+             
+             (define-syntax-class name-clause
+               #:description (format "~a" 'name)
+               #:literals (name)
+               #:attributes (proc rate ...)
+               (pattern (name proc0:expr)
+                        #:with (rate0 ...) (map (lambda (x) #'0) '(rate0 ...))
+                        #:with proc #'(world->world proc0)
+                        thing ... ...)
+               (pattern (on-tick proc0:expr (~var rate0 expr) ...)
+                        #:with proc #'(world->world> proc0)
+                        thing ... ...))
+             )))]))
+  
+  (define-clause on-mouse (proc world-nat-nat-mouse->world))
+  (define-clause on-tick (proc world->world) (rate (lambda (x) 1/28)))
+  
+  ;; --- on-tick --- 
+  #|
+  (define-syntax (on-tick . x)
+    (raise-syntax-error 'on-tick "used out of context" x))
+  
+  (define-syntax-class on-tick-clause 
+    #:description "on tick"
+    #:literals (on-tick)
+    #:attributes (proc rate)
+    (pattern (on-tick proc0:expr)
+             #:with proc #'(world->world proc0)
+             #:with rate #'1/28)
+    (pattern (on-tick proc0:expr rate0:expr)
+             #:with proc #'(world->world> proc0)
+             #:with rate #'(positive-number> rate0)))
+  
+  (provide on-tick on-tick-clause)
+  |#
+  ;; --- on-draw --- 
+  (define-syntax (on-draw . x)
+    (raise-syntax-error 'on-draw "used out of context" x))
+  
+  (define-syntax-class on-draw-clause 
+    #:description "on draw"
+    #:literals (on-draw)
+    #:attributes (proc width height)
+    (pattern (on-draw proc0:expr)
+             #:with proc #'(wrap worldxkey->world proc0)
+             #:with width #'#f
+             #:with height #'#f)
+    (pattern (on-draw proc0:expr width0:expr height0:expr)
+             #:with proc #'(worldxkey->world> proc0)
+             #:with width #'(natural-number> width0)
+             #:with height #'(natural-number> height0)))
+  
+  (provide on-draw on-draw-clause))
+
+(module utest scheme 
+  (require (for-syntax syntax/parse 'clauses))
+  
+  (define-syntax (big-bang stx)
+    (syntax-parse stx
+      [(big-bang world0:expr 
+                 (~or (~optional otc:on-tick-clause)
+                      ; (~optional omc:on-mouse-clause)
+                      (~optional odc:on-draw-clause))
+                 ...)
+       #`(printf "~s\n"
+                 '(bb world0
+                      #,(if (attribute otc)
+                            #'otc.rate 
+                            #'1/28)
+                      #,(if (attribute odc)
+                            #'odc.proc
+                            #''not-draw)))]))
+  
+  (big-bang 0)   
+  (big-bang 1 (on-tick add1))
+  (big-bang 2 (on-tick add1 1/2))
+  (big-bang 3 (on-draw add1 1/2 1/3))
+  (big-bang 4 (on-mouse add1 1 2))
+  )
+
+(require 'utest)

collects/2htdp/universe.ss

@@ -7,8 +7,6 @@
    -- take out counting; replace by 0.25 delay
 
    -- make window resizable :: why
-   -- what if clauses are repeated in world and/or universe descriptions? 
-   -- what if the initial world or universe state is omitted? the error message is bad then. 
 |#
 
 (require (for-syntax "private/syn-aux.ss" scheme/function)