From 5efe086d06de531d4b17284879513e150d6a41ea Mon Sep 17 00:00:00 2001
From: Sergiu Ivanov <sivanov@colimite.fr>
Date: Wed, 27 Apr 2022 00:15:03 +0200
Subject: [PATCH] Add UpdateFunction and DomainMapping.

---
 networks.rkt               |  4 +++-
 scribblings/networks.scrbl | 14 ++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/networks.rkt b/networks.rkt
index 41893ff..217c110 100644
--- a/networks.rkt
+++ b/networks.rkt
@@ -5,9 +5,11 @@
            typed/graph racket/random)
 
   (provide
-   State)
+   State UpdateFunction DomainMapping)
 
   (define-type (State a) (VariableMapping a))
+  (define-type (UpdateFunction a) (-> (State a) a))
+  (define-type (DomainMapping a) (VariableMapping (Listof a)))
   )
 
 (require 'typed)
diff --git a/scribblings/networks.scrbl b/scribblings/networks.scrbl
index 5910cfb..ac98c4f 100644
--- a/scribblings/networks.scrbl
+++ b/scribblings/networks.scrbl
@@ -34,6 +34,20 @@ the variables.  A synonym of @racket[VariableMapping].
 
 }
 
+@defform[(UpdateFunction a)]{
+
+An update function is a function computing a value from the given
+state.  This is a synonym of the type @racket[(-> (State a) a)].
+
+}
+
+@defform[(DomainMapping a)]{
+
+A domain mapping is a hash table mapping variables to the lists of values in
+their domains.
+
+}
+
 @section{Syntactic description of networks}
 
 @section{Inferring interaction graphs}