New function: endp.

This improves compatibility with other Lisp dialects
in a small way.

* eval.c (eval_init): Register endp intrinsic.

* lib.c (endp): New function.

* lib.h (endp): Declared.

* txr.1: Documented endp.

1 files changed, 25 insertions, 0 deletions

diff --git a/txr.1 b/txr.1
index ca74fe48..549a7da3 100644
--- a/txr.1
+++ b/txr.1
@@ -17046,6 +17046,31 @@ installations should use
 .codn proper-listp ,
 but its use going forward is deprecated.
 
+.coNP Function @ endp
+.synb
+.mets (endp << object )
+.syne
+.desc
+The
+.code endp
+function returns
+.code t
+if
+.meta object
+is the object
+.codn nil .
+
+If
+.meta object
+is a cons cell, then
+.code endp
+returns
+.codn t .
+
+Otherwise,
+.code endp
+function throws an exception.
+
 .coNP Function @ length-list
 .synb
 .mets (length-list << list )