Updates to files, about to reshuffle names

collects/schelog/INSTALL

@@ -1,5 +1,13 @@
 Installing Schelog
 
+
+*** JBC, 2010-04-22: I conjecture that (as a collection
+within the PLT tree) installation directions are now
+superfluous.  The below is preserved for posterity.
+
+
+
+
 -
 
 First, obtain the Schelog distribution.  This is

collects/schelog/README

@@ -3,6 +3,14 @@ Schelog
 Dorai Sitaram
 ds26@gte.com
 
+
+*** JBC 2010-04-22: this package has been TAMPERED WITH in an unscrupulous and
+undisciplined way by John Clements 2010-04-22 in order to see how difficult it
+would be to get it to compile in PLT 4.2.5.  The answer is "not hard", but it's
+certainly not portable any more, and crucially the two macros that cause
+capture of the ! symbol now require uses of the macro to supply the bang, thus
+making them non-capturing.
+
                           ...
 
 Schelog is for you if you are interested in any or all
@@ -37,9 +45,3 @@ produces a directory called "schelog".  In it is a file
 called INSTALL which contains detailed installation
 instructions.  Read INSTALL now.
 
-*** this package has been TAMPERED WITH in an unscrupulous and undisciplined
-way by John Clements 2010-04-22 in order to see how difficult it would be to
-get it to compile in PLT 4.2.5.  The answer is "not hard", but it's certainly
-not portable any more, and crucially the two macros that cause capture of 
-the ! symbol now require uses of the macro to supply the bang, thus making them
-non-capturing.

collects/schelog/examples/bible.scm

@@ -1,10 +1,15 @@
+#lang racket
+
+(require "../schelog.scm"
+         schemeunit)
+
 ;The following is the "Biblical" database from "The Art of
 ;Prolog", Sterling & Shapiro, ch. 1.
 
 ;(%father X Y) :- X is the father of Y.
 
 (define %father
-  (%rel ()
+  (%rel ! ()
     (('terach 'abraham)) (('terach 'nachor)) (('terach 'haran))
     (('abraham 'isaac)) (('haran 'lot)) (('haran 'milcah))
     (('haran 'yiscah))))
@@ -12,14 +17,14 @@
 ;(%mother X Y) :- X is the mother of Y.
 
 (define %mother
-  (%rel () (('sarah 'isaac))))
+  (%rel ! () (('sarah 'isaac))))
 
 (define %male
-  (%rel ()
+  (%rel ! ()
     (('terach)) (('abraham)) (('isaac)) (('lot)) (('haran)) (('nachor))))
 
 (define %female
-  (%rel ()
+  (%rel ! ()
     (('sarah)) (('milcah)) (('yiscah))))
 
 ;AoP, ch. 17.  Finding all the children of a particular
@@ -31,13 +36,13 @@
 (define %children-1
 
   (letrec ((children-aux
-	     (%rel (x a cc c)
+	     (%rel ! (x a cc c)
 	       ((x a cc)
                  (%father x c) (%not (%member c a)) !
                  (children-aux x (cons c a) cc))
 	       ((x cc cc)))))
 
-    (%rel (x cc)
+    (%rel ! (x cc)
       ((x cc) (children-aux x '() cc)))))
 
 (define terachs-kids-test
@@ -47,6 +52,9 @@
     (%which (cc)
       (%children-1 'terach cc))))
 
+(check-equal? (terachs-kids-test)
+              `((cc (haran nachor abraham))))
+
 (define dad-kids-test
   ;find a father and all his children.  Returns
   ;f = terach, cc = (haran nachor abraham).
@@ -56,6 +64,9 @@
     (%which (f cc)
       (%children-1 f cc))))
 
+(check-equal? (dad-kids-test)
+              `((f terach) (cc (haran nachor abraham))))
+
 (define terachs-kids-test-2
   ;find all the kids of Terach, using %set-of.
   ;returns kk = (abraham nachor haran)
@@ -68,7 +79,7 @@
 ;Uses set predicate %bag-of
 
 (define %children
-  (%rel (x kids c)
+  (%rel ! (x kids c)
     ((kids) (%set-of c (%father x c) kids))))
 
 (define dad-kids-test-2

collects/schelog/makefile

@@ -1,3 +1,7 @@
+# JBC, 2010-04-22:
+# this makefile could probably be usefully rendered in scheme... but
+# I'm not going to try.
+
 
 TRIGGER_FILES = history manifest makefile version.tex \
 		schelog.scm schelog.tex

collects/schelog/schelog.scm

@@ -1,7 +1,27 @@
-#lang scheme
+#lang racket
+
+
+;; TODO: figure out what should actually be 'provide'd.
 
 (provide (all-defined-out))
 
+;; A Note on changes: define-macro isn't so nice, but 
+;; someone (Dorai?) helpfully provided commented-out
+;; versions of each macro in syntax-rules style.  
+;; Unfortunately, they didn't compile, but this seemed
+;; related to an inability to capture the '!' name.
+;; The easiest way to fix this was just to take the 
+;; classic "make 'em put the identifier in there" approach,
+;; which means that uses of cut and rel must now include 
+;; a bang explicitly.  It wouldn't be too hard to change
+;; back to a capturing macro; I know syntax-case can do
+;; it, I don't know if syntax-rules can. 
+
+;; Also, I changed a few top-level mutable bindings into
+;; boxed bindings. 
+
+;;-- JBC, 2010-04-22
+
 
 ;MzScheme version of
 ;schelog.scm
@@ -718,12 +738,12 @@
 ;the above could also have been written in a more
 ;Prolog-like fashion, viz.
 
-'(define %member
+#;'(define %member
   (%rel ! (x xs y ys)
     ((x (cons x xs)))
     ((x (cons y ys)) (%member x ys))))
 
-'(define %if-then-else
+#;'(define %if-then-else
   (%rel ! (p q r)
     ((p q r) p ! q)
     ((p q r) r)))
@@ -742,8 +762,11 @@
 
 ; deprecated names -- retained here for backward-compatibility
 
-(define == %=)
-(define %notunify %/=)
+;; JBC, 2010-04-22 -- don't think backward compatibility counts any more. commenting 
+;; these out.
+
+#;(define == %=)
+#;(define %notunify %/=)
 
 #;(define-macro %cut
   (lambda e