From 458ba10ab5e77891281656c8c89abf3805b0e7dc Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Sun, 1 May 2022 01:05:35 +0200
Subject: [PATCH] Add 01->boolean/state (replacing booleanize-state).

---
 networks.rkt               | 27 +++++++++++++--------------
 scribblings/networks.scrbl | 11 +++++++++++
 2 files changed, 24 insertions(+), 14 deletions(-)

diff --git a/networks.rkt b/networks.rkt
index 9e8640b..48640ee 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -9,8 +9,9 @@
 
   (provide
    State UpdateFunction Domain DomainMapping
-   (struct-out network) Network
+   01->boolean/state
 
+   (struct-out network) Network
    make-same-domains make-boolean-domains make-boolean-network
    make-01-domains make-01-network update)
 
@@ -19,6 +20,16 @@
   (define-type (Domain a) (Listof a))
   (define-type (DomainMapping a) (VariableMapping (Domain a)))
 
+  (: 01->boolean/state (-> (State (U Zero One)) (State Boolean)))
+  (define (01->boolean/state s)
+    (for/hash ([(x val) (in-hash s)]) : (State Boolean)
+              (if (eq? val 1) (values x #t) (values x #f))))
+
+  (module+ test
+    (test-case "01->boolean/state"
+      (check-equal? (01->boolean/state (hash 'a 0 'b 1))
+                    (hash 'a #f 'b #t))))
+
   (struct (a) network ([functions : (VariableMapping (UpdateFunction a))]
                        [domains : (DomainMapping a)])
     #:transparent
@@ -122,8 +133,7 @@
                [struct network-form ([forms variable-mapping?]
                                      [domains domain-mapping/c])])
  ;; Functions
- (contract-out [booleanize-state (-> state? state?)]
-               [update-function-form->update-function (-> update-function-form? update-function/c)]
+ (contract-out [update-function-form->update-function (-> update-function-form? update-function/c)]
                [network-form->network (-> network-form? network?)]
                [make-boolean-network-form (-> variable-mapping? network-form?)]
                [forms->boolean-network (-> variable-mapping? network?)]
@@ -266,17 +276,6 @@
 ;;; values in their domains.
 (define domain-mapping/c (hash/c variable? list?))
 
-;;; Booleanizes a given state: replaces 0 with #f and 1 with #t.
-(define (booleanize-state s)
-  (for/hash ([(x val) s]) (match val [0 (values x #f)] [1 (values x #t)])))
-
-(module+ test
-  (test-case "make-state, make-state-booleanize, booleanize-state"
-    (check-equal? (make-state-booleanize '((a . 0) (b . 1)))
-                  (make-state '((a . #f) (b . #t))))
-    (check-equal? (booleanize-state (make-state '((a . 0) (b . 1))))
-                  (make-state '((a . #f) (b . #t))))))
-
 
 ;;; =================================
 ;;; Syntactic description of networks
diff --git a/scribblings/networks.scrbl b/scribblings/networks.scrbl
index 40c8f32..ceaa80a 100644
--- a/scribblings/networks.scrbl
+++ b/scribblings/networks.scrbl
@@ -97,6 +97,17 @@ two variables @racket[a] and @racket[b] whose values are in @tt{{0,1}}:
                (U Zero One)))
 ]
 
+@section{Utilities}
+
+@defproc[(01->boolean/state [s (State (U Zero One))]) (State Boolean)]{
+
+Converts the values 0 and 1 in a state to @racket[#f] and
+@racket[#t] respectively.
+
+@ex[
+(01->boolean/state (hash 'a 0 'b 1))
+]}
+
 @section{Networks}
 
 @defstruct*[network ([functions (VariableMapping (UpdateFunction a))]