lib: deprecate set-diff; extend set operations.

* eval.c (eval_init): Register set-diff under two
names: set-diff and diff. Register new isec and uni
intrinsics.

* lib.c (isec, uni): New functions.

* lib.h (isec, uni): Declared.

* txr.1: Documented new uni and isec functions, new diff
function name, and the deprecation of set-diff and its order
guarantee w.r.t the left sequence.

1 files changed, 2 insertions, 0 deletions

diff --git a/lib.h b/lib.h
index 9b8c997b..c1a898c2 100644
--- a/lib.h
+++ b/lib.h
@@ -1029,6 +1029,8 @@ val drop_while(val pred, val seq, val keyfun);
 val drop_until(val pred, val seq, val keyfun);
 val in(val seq, val key, val testfun, val keyfun);
 val set_diff(val list1, val list2, val testfun, val keyfun);
+val isec(val list1, val list2, val testfun, val keyfun);
+val uni(val list1, val list2, val testfun, val keyfun);
 val copy(val seq);
 val length(val seq);
 val empty(val seq);