* eval.c (ap_s, ret_s, aret_s): New symbol variables.

(me_ret): Static function renamed to me_ret_aret.
Handles ret and aret macro expansion.
(eval_init): Initialize ap_s, ret_s and aret_s.
Re-register ret macro using ret_s and bind to me_ret_aret.
Register aret macro.

* txr.1: Documented aret.

* tl.vim, txr.vim: Regenerated.

1 files changed, 42 insertions, 0 deletions

diff --git a/txr.1 b/txr.1
index 70db9229..ac35cf22 100644
--- a/txr.1
+++ b/txr.1
@@ -20880,6 +20880,48 @@ and the expression
 returns a function similar to
 .codn (lambda (. rest) 42) .
 
+.coNP Macro @ aret
+.synb
+.mets (aret << form )
+.syne
+.desc
+The
+.code ret
+macro's
+.meta form
+argument is treated similarly to the second and subsequent arguments of the
+.code op
+operator.
+
+The
+.code aret
+macro produces a function which takes any number of arguments,
+and returns the value specified by
+.metn form .
+
+.meta form
+can contain
+.code ap
+meta syntax like
+.meta @n
+and
+.codn @rest .
+
+The following equivalence holds:
+
+.cblk
+  (aret x) <--> (ap identity x))
+.cble
+
+Thus the expression
+.code (aret @2)
+returns a function similar to
+.codn (lambda (. rest) (second rest)) ,
+and the expression
+.code (aret 42)
+returns a function similar to
+.codn (lambda (. rest) 42) .
+
 .coNP Functions @ chain and @ chand
 .synb
 .mets (chain << func *)