Logtalk 2.25.0 files.

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1288 b08c6af1-5177-4d33-ba66-4b1c6b8b522a

Logtalk/examples/engines/NOTES

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.24.0
+Release 2.25.0
 
 Copyright (c) 1998-2005 Paulo Moura.  All Rights Reserved.
 =================================================================
@@ -10,4 +10,4 @@ To load this example and for sample queries, please see the SCRIPT
 file.
 
 For a description of this example, please see the comments in the 
-engines.mlgt metafile.
+engines.lgt source file.

Logtalk/examples/engines/SCRIPT

@@ -1,6 +1,6 @@
 =================================================================
 Logtalk - Object oriented extension to Prolog
-Release 2.24.0
+Release 2.25.0
 
 Copyright (c) 1998-2005 Paulo Moura.  All Rights Reserved.
 =================================================================

Logtalk/examples/engines/engines.lgt

@@ -0,0 +1,67 @@
+/*
+This is a simple example of category composition, i.e. importation of 
+categories by other categories in order to provide modified components 
+for building objects, using car engines.
+
+The example defines a car engine protocol (enginep), a standard engine 
+(classic), and an improved version of it (sport). Both engines are then 
+imported in two car models (sedan and coupe).
+*/
+
+
+% first we define a protocol for describing the characteristics of an engine:
+
+:- protocol(enginep).
+
+	:- public(reference/1).
+	:- public(capacity/1).
+	:- public(cylinders/1).
+	:- public(horsepower_rpm/2).
+	:- public(bore_stroke/2).
+	:- public(fuel/1).
+
+:- end_protocol.
+
+
+% second, we can define a typical engine as a category, which will be used 
+% when "assembling" cars:
+
+:- category(classic,
+	implements(enginep)).
+
+	reference('M180.940').
+	capacity(2195).
+	cylinders(6).
+	horsepower_rpm(94, 4800).
+	bore_stroke(80, 72.8).
+	fuel(gasoline).
+
+:- end_category.
+
+
+% next, we define a souped up version of the previous engine, which differs 
+% from the standard one only in its reference and in its horsepower:
+
+:- category(sport,
+	imports(classic)).
+
+	reference('M180.941').
+	horsepower_rpm(110, 5000).
+
+:- end_category.
+
+
+% with engines (and other components), we may start "assembling" some cars:
+
+:- object(sedan,
+	imports(classic)).
+
+
+:- end_object.
+
+
+:- object(coupe,
+	imports(sport)).
+
+
+:- end_object.