From f0a7c270e9b0af6587c16c062d342a045414139e Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Tue, 18 Feb 2020 12:16:03 +0100
Subject: [PATCH] bn: Add make-bn-forms.

---
 bn-tests.rkt |  8 +++++---
 bn.rkt       | 13 ++++++++++++-
 2 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/bn-tests.rkt b/bn-tests.rkt
index dc65f01..a4c69d8 100644
--- a/bn-tests.rkt
+++ b/bn-tests.rkt
@@ -36,7 +36,9 @@
         (let ([s (make-state '((x . #t) (y . #f)))]
               [f (update-func-form->update-func '(and x y))])
           (check-equal? (f s) #f))
-        (let ([bn (bn-form->bn (make-hash '((a . (and a b)) (b . (not b)))))]
+        (let ([bn1 (bn-form->bn (make-hash '((a . (and a b)) (b . (not b)))))]
+              [bn2 (make-bn-forms '((a . (and a b))
+                                    (b . (not b))))]
               [s (make-state '((a . #t) (b . #t)))])
-          (check-equal? ((hash-ref bn 'a) s)
-                        #t))))))
+          (check-equal? ((hash-ref bn1 'a) s) #t)
+          (check-equal? ((hash-ref bn2 'a) s) #t))))))
diff --git a/bn.rkt b/bn.rkt
index 035ac4e..2164c9f 100644
--- a/bn.rkt
+++ b/bn.rkt
@@ -11,7 +11,7 @@
 
 (provide Variable State UpdateFunc Network
          update make-state make-bn-funcs update-func-form->update-func
-         bn-form->bn)
+         bn-form->bn make-bn-forms)
 
 
 ;;; =================
@@ -80,3 +80,14 @@
   (make-hash
    (hash-map bnf (lambda ([x : Variable] [form : UpdateFuncForm])
                    (cons x (update-func-form->update-func form))))))
+
+;;; Build a network from a list of pairs of forms of update functions.
+(: make-bn-forms (-> (Listof (Pairof Variable UpdateFuncForm)) Network))
+(define (make-bn-forms forms)
+  (bn-form->bn (make-hash forms)))
+
+(let ([bn (make-bn-forms '((a . (and a b))
+                           (b . (not b))))]
+      [s (make-state '((a . #t)
+                       (b . #t)))])
+  ((hash-ref bn 'a) s))