921e576877
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@1138 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
68 lines
1.4 KiB
Plaintext
68 lines
1.4 KiB
Plaintext
/*
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This is a simple example of category composition, i.e. importation of
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categories by other categories in order to provide modified components
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for building objects, using car engines.
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The example defines a car engine protocol (enginep), a standard engine
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(classic), and an improved version of it (sport). Both engines are then
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imported in two car models (sedan and coupe).
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*/
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% first we define a protocol for describing the characteristics of an engine:
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:- protocol(enginep).
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:- public(reference/1).
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:- public(capacity/1).
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:- public(cylinders/1).
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:- public(horsepower_rpm/2).
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:- public(bore_stroke/2).
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:- public(fuel/1).
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:- end_protocol.
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% second, we can define a typical engine as a category, which will be used
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% when "assembling" cars:
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:- category(classic,
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implements(enginep)).
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reference('M180.940').
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capacity(2195).
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cylinders(6).
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horsepower_rpm(94, 4800).
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bore_stroke(80, 72.8).
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fuel(gasoline).
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:- end_category.
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% next, we define a souped up version of the previous engine, which differs
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% from the standard one only in its reference and in its horsepower:
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:- category(sport,
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imports(classic)).
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reference('M180.941').
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horsepower_rpm(110, 5000).
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:- end_category.
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% with engines (and other components), we may start "assembling" some cars:
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:- object(sedan,
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imports(classic)).
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:- end_object.
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:- object(coupe,
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imports(sport)).
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:- end_object.
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