1 files changed, 6 insertions, 0 deletions
diff --git a/lib.c b/lib.c
index 68634b4f..ca6c6fe2 100644
--- a/lib.c
+++ b/lib.c
@@ -3616,6 +3616,12 @@ val keep_keys_if(val pred, val seq, val keyfun_in, val mapfun_in)
   return rem_if_impl(notf(pred), seq, keyfun_in, mapfun, lit("keep-keys-if"));
 }
 
+val keep(val obj, val seq, val testfun_in, val keyfun_in, val mapfun_in)
+{
+  val testfun = default_arg(testfun_in, equal_f);
+  return remov(obj, seq, notf(testfun), keyfun_in, mapfun_in);
+}
+
 val separate(val pred, val seq, val keyfun_in)
 {
   val self = lit("separate");