From: LeonardoBizzoni <leo2002714@gmail.com>
Date: Sun, 17 Dec 2023 09:35:58 +0000 (+0100)
Subject: Fatta la `fieldx`
X-Git-Url: http://git.leonardobizzoni.com/?a=commitdiff_plain;h=21de6f1b15d029984de6988e2968d2883cad14ce;p=ObjectOriented-Prolog-Lisp

Fatta la `fieldx`
---

diff --git a/Prolog/README.org b/Prolog/README.org
index 560b835..e9d4925 100644
--- a/Prolog/README.org
+++ b/Prolog/README.org
@@ -107,7 +107,7 @@ make(InstanceName, ClassName, Fields) :-
     is_instance(InstanceName, ClassName),
     check_fields(InstanceName, Fields).
 
-check_fields(InstanceName, []).
+check_fields(_InstanceName, []).
 check_fields(InstanceName, [=(Field, Value) | Other]) :-
     field(InstanceName, Field, Value),
     check_fields(InstanceName, Other).
@@ -127,12 +127,21 @@ check_fields(InstanceName, [=(Field, Value) | Other]) :-
 
 *** Esempio pratico
 
-** fields
+** fieldx
 *** Definizione
-
+- Non ho capito se così va bene
+- Non ho capito a cosa serve
+- Non ho capito quando va usato
 
 *** Implementazione
 #+begin_src prolog :tangle oop.pl
+fieldx(Instance, [FieldName], Res) :-
+    field(Instance, FieldName, Res),
+    !.
+fieldx(Instance, [FieldName | Others], Res) :-
+    is_instance(Instance),
+    field(Instance, FieldName, Value),
+    fieldx(Value, Others, Res).
 #+end_src
 
 *** Esempio pratico
diff --git a/Prolog/oop.pl b/Prolog/oop.pl
index 24325bc..452d766 100644
--- a/Prolog/oop.pl
+++ b/Prolog/oop.pl
@@ -81,14 +81,20 @@ make(InstanceName, ClassName, Fields) :-
     is_instance(InstanceName, ClassName),
     check_fields(InstanceName, Fields).
 
-check_fields(InstanceName, []).
+check_fields(_InstanceName, []).
 check_fields(InstanceName, [=(Field, Value) | Other]) :-
     field(InstanceName, Field, Value),
     check_fields(InstanceName, Other).
 
 :- dynamic field/3.
 
-
+fieldx(Instance, [FieldName], Res) :-
+    field(Instance, FieldName, Res),
+    !.
+fieldx(Instance, [FieldName | Others], Res) :-
+    is_instance(Instance),
+    field(Instance, FieldName, Value),
+    fieldx(Value, Others, Res).
 
 :- dynamic is_class/1.
 :- dynamic is_child_of/2.