various fixes

2019-04-22 21:28:33 -06:00
parent 535465fcd4
commit a5dc7f2387
7 changed files with 148 additions and 136 deletions
--- a/src/prolog/lib/between.pl
+++ b/src/prolog/lib/between.pl
@@ -5,9 +5,14 @@
 :- use_module(library(lists), [length/2]).
 :- use_module(library(error)).

-between(Lower, Upper, Lower) :-
+between(Lower, Upper, X) :-
+    must_be(integer, Lower),
+    must_be(integer, Upper),
+    between_(Lower, Upper, X).
+
+between_(Lower, Upper, Lower) :-
    Lower =< Upper.
-between(Lower1, Upper, X) :-
+between_(Lower1, Upper, X) :-
    Lower1 < Upper,
    Lower2 is Lower1 + 1,
    between(Lower2, Upper, X).