corner cases in new, refs #3

mlliarm · Nov 9, 2020 · bd2ed46 · bd2ed46
1 parent cba773c
commit bd2ed46
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/interval_arithmetic.lgt b/interval_arithmetic.lgt
@@ -2,8 +2,13 @@
 		implements(interval_arithmeticp)).
 
 	new(Start, End, Interval) :-
+        Start \= End,
 		Interval = [Start, End].
 
+    new(Start, End, Interval) :-
+        Start < End,
+        Interval = [Start, End].
+
     	is_in([Xa, Xb], Number) :-
         	Xa =< Number,
         	Xb >= Number.