git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@561 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
		
			
				
	
	
		
			58 lines
		
	
	
		
			840 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
			
		
		
	
	
			58 lines
		
	
	
		
			840 B
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| 
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| :- object(date(_Year, _Month, _Day)).
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| 
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| 
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| 	:- info([
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| 		version is 1.0,
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| 		authors is 'Paulo Moura',
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| 		date is 1998/3/23,
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| 		comment is 'Dates as parametric objects.',
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| 		parnames is ['Year', 'Month', 'Day']]).
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| 
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| 
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| 	:- public(year/1).
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| 	:- mode(year(?integer), one).
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| 
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| 	:- public(month/1).
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| 	:- mode(month(?integer), one).
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| 
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| 	:- public(day/1).
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| 	:- mode(day(?integer), one).
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| 
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| 	:- public(today/0).
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| 	:- mode(today, one).
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| 
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| 	:- public(leap_year/0).
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| 	:- mode(leap_year, zero_or_one).
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| 
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| 
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| 	year(Year) :-
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| 		parameter(1, Year).
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| 
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| 
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| 	month(Month) :-
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| 		parameter(2, Month).
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| 
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| 
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| 	day(Day) :-
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| 		parameter(3, Day).
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| 
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| 
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| 	today :-
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| 		{'$lgt_current_date'(Year, Month, Day)},
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| 		parameter(1, Year),
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| 		parameter(2, Month),
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| 		parameter(3, Day).
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| 
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| 
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| 	leap_year :-
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| 		parameter(1, Year),
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| 		(0 is mod(Year, 4),
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| 		 0 is mod(Year, 100)
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| 		 ;
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| 		 0 is mod(Year, 400)),
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| 		!.
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| 
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| 
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| :- end_object.
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