diff: set_bbbtree__subset

[Fergus Henderson]

library/set_bbbtree.m:
	Change the order of the arguments to set_bbbtree__subset,
	to match the order in set.m and elsewhere.

NEWS:
	Document the above change.

Index: set_bbbtree.m
===================================================================
RCS file: /home/staff/zs/imp/mercury/library/set_bbbtree.m,v
retrieving revision 1.7
diff -u -r1.7 set_bbbtree.m
--- set_bbbtree.m	1997/05/21 02:16:23	1.7
+++ set_bbbtree.m	1997/07/08 16:25:19
@@ -233,14 +233,14 @@
 
 
 	% `set_bbbtree__subset(SetA, SetB)' is true iff all the elements of
-	% `SetB' are also elements of `SetA'.
+	% `SetA' are also elements of `SetB'.
 
 :- pred set_bbbtree__subset(set_bbbtree(T), set_bbbtree(T)).
 :- mode set_bbbtree__subset(in, in) is semidet.
 
 
 	% `set_bbbtree__superset(SetA, SetB)' is true iff all the elements of
-	% `SetA' are also elements of `SetB'.
+	% `SetB' are also elements of `SetA'.
 
 :- pred set_bbbtree__superset(set_bbbtree(T), set_bbbtree(T)).
 :- mode set_bbbtree__superset(in, in) is semidet.
@@ -864,7 +864,7 @@
 %------------------------------------------------------------------------------%
 
 set_bbbtree__subset(SetA, SetB) :-
-	set_bbbtree__difference(SetB, SetA, Set),
+	set_bbbtree__difference(SetA, SetB, Set),
 	set_bbbtree__empty(Set).
 
 %------------------------------------------------------------------------------%
Index: ../NEWS
===================================================================
RCS file: /home/staff/zs/imp/mercury/NEWS,v
retrieving revision 1.57
diff -u -r1.57 NEWS
--- NEWS	1997/07/01 01:39:39	1.57
+++ NEWS	1997/07/08 16:34:49
@@ -147,7 +147,7 @@
     We've also added io__nl/3 to print a newline.
     Together with the change to make module qualifiers optional,
     these changes make performing output quite a bit simpler;
-    it's nice that `print("Foo = "), print(Foo), nl' works now.
+    it's nice to be able to write `print("Foo = "), print(Foo), nl'.
 
   - term_to_type/2 and type_to_term/2 are now implemented.
 
@@ -155,7 +155,7 @@
     The predicate report_stats, which used to be in std_util, is now
     in this module.
 
-  - The interface to the relation module has been changed extensively.
+  - The interface to the relation.m module has been changed extensively.
     Elements must now be explicitly added to the domain of the relation,
     using relation__add_element/4, and relation operations such as
     relation__add are now performed on relation_keys.  There are also
@@ -164,7 +164,11 @@
 	relation__search_element/3, relation__lookup_element/3,
 	relation__search_key/3, and relation__lookup_key/3
 
-  - set__subset XXX
+  - We changed the order of the arguments to set_bbbtree__subset,
+    for consistency with the order in set__subset and elsewhere.
+    We also changed the implementation of set__subset and
+    set_ordlist__subset to match the behaviour specified in the
+    documentation.
 
   - We made some extensive additions to bag.m to include the standard set
     operations (union, intersection, subtraction), and some other predicates
-- 
Fergus Henderson <fjh at cs.mu.oz.au>   |  "I have always known that the pursuit
WWW: <http://www.cs.mu.oz.au/~fjh>   |  of excellence is a lethal habit"
PGP: finger fjh at 128.250.37.3         |     -- the last words of T. S. Garp.