From 0a344194aa717aeff7079560ed1624c97066447b Mon Sep 17 00:00:00 2001
From: Kaz Kylheku <kaz@kylheku.com>
Date: Sun, 24 Jan 2021 13:23:51 -0800
Subject: doc: add back discussion about (rcons ...) pattern.

* txr.1: Add anote that a pattern a..b matches rcons syntax,
and add examples.

* tests/011/patmatch.tl: new examples from doc added as tests.
---
 tests/011/patmatch.tl |  3 +++
 txr.1                 | 13 +++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/tests/011/patmatch.tl b/tests/011/patmatch.tl
index ac474738..c9326eda 100644
--- a/tests/011/patmatch.tl
+++ b/tests/011/patmatch.tl
@@ -144,3 +144,6 @@
 (test (when-match #R(1 @a) 1..2 a) 2)
 (test (when-match #R(2 @a) 1..2 a) nil)
 (test (when-match #R(@a 1) 1..2 a) nil)
+
+(test (when-match @a..@b '1..2 (list a b)) (1 2))
+(test (when-match (rcons @a @b) '(rcons 1 2) (list a b)) (1 2))
diff --git a/txr.1 b/txr.1
index 99e03045..3d64f752 100644
--- a/txr.1
+++ b/txr.1
@@ -39878,6 +39878,12 @@ is matched against its
 .code to
 part.
 
+Note that if the range expression notation
+.code a..b
+is used as a pattern, that is actualy a list pattern, due to
+that being a syntactic sugar for
+.codn "(rcons a b)" .
+
 .TP* Examples:
 
 .verb
@@ -39886,6 +39892,13 @@ part.
   (if-match #R(10 20) #R(1 2) :yes :no) -> :no
 
   (when-match #R(@a @b) 1..2 (list a b)) -> (1 2)
+
+  ;; not a range match! rcons syntax match
+  (when-match @a..@b '1..2 (list a b)) -> (1 2)
+
+  ;; above, de-sugared:
+  (when-match (rcons @a @b) (rcons 1 2) (list a b)) -> (1 2)
+
 .brev
 
 .coNP Pattern operator @ struct
-- 
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