fd048651b6
git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@55 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
25 lines
426 B
Plaintext
25 lines
426 B
Plaintext
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:- object(metric(_Town)).
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:- info([
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authors is 'Paulo Moura',
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version is 1.0,
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date is 2000/4/22,
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comment is '.',
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parnames is ['Town'],
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source is 'Example adopted from the Francis G. McCabe L&O documentation.']).
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:- public(less/2).
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less((Town1, _), (Town2, _)):-
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parameter(1, Town),
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Town::crow_flies(Town1, Distance1),
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Town::crow_flies(Town2, Distance2),
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Distance1 < Distance2.
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:- end_object.
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