From 3fbb5bf2be99ab52d5c927c3d467b8d1412abdaf Mon Sep 17 00:00:00 2001
From: Kaz Kylheku <kaz@kylheku.com>
Date: Tue, 26 Oct 2021 19:07:10 -0700
Subject: match: unquoted quasiliteral patterns don't work.

* tests/011/patmatch.tl: Add failing test cases.

* txr.1: Document desired requirements.
---
 tests/011/patmatch.tl |  5 +++++
 txr.1                 | 26 ++++++++++++++++++++++++++
 2 files changed, 31 insertions(+)

diff --git a/tests/011/patmatch.tl b/tests/011/patmatch.tl
index 09d294a8..da2f8de4 100644
--- a/tests/011/patmatch.tl
+++ b/tests/011/patmatch.tl
@@ -526,3 +526,8 @@
   (eval-only
     (compile-file (base-name *load-path*) "temp.tlo")
     (remove-path "temp.tlo")))
+
+(mtest
+  (match @`foo-@a` "foo-abc" a) "abc"
+  (match ^(,`foo-@a`) '("foo-abc") a) "abc"
+  (match  ^#J[~`foo-@a`] #("foo-abc") a) "abc")
diff --git a/txr.1 b/txr.1
index e41b36ff..f51f0740 100644
--- a/txr.1
+++ b/txr.1
@@ -42369,6 +42369,7 @@ that being a syntactic sugar for
 .NP* Quasiliteral match
 .synb
 .mets <> "`...@" var "...`"
+.mets <> @"`...@" var "...`"
 .syne
 .desc
 The quasiliteral syntax is supported as a pattern-matching operator.
@@ -42380,6 +42381,18 @@ object isn't a string according to
 then the match fails. The quasiliteral pattern must match the entire
 input string.
 
+In order that the quasiliteral's syntactic structure is not misinterpreted
+as a predicate pattern, and in order to make certain situations work
+in quasiquoted pattern matching, a quasiliteral pattern may be specified
+as either
+.code "`...`"
+or
+.codn "@`...`" .
+The latter form, which is structurally
+.code "(sys:expr (sys:quasi ...))"
+is specially recognized and treated as equivalent to the unadorned
+quasiliteral pattern.
+
 A quasiliteral pattern matches in a linear fashion, from left to right.
 Variables bound earlier in the pattern can be referenced later in the pattern
 as bound variables.
@@ -42571,10 +42584,23 @@ otherwise it is translated to the
 .meti (sys:expr << expr )
 .onom
 syntax.
+.coIP ",`...quasilit...`"
+An unquoted quasiliteral is treated uniformly as
+.mono
+.meti >> , expr
+.onom
+and is therefore translated into
+.codn "@`...quasilit...`" .
+Since that is equivalent to
+.codn "`...quasilit...`" ,
+quasiteral matching is supported within quasiquote notation
+in a straightforward way.
 .meIP >> ~ expr
 In JSON syntax, unquotes are given the same above treatment as
 .code ,
 (comma) unquotes in ordinary syntax.
+.coIP ~`...quasilit...`
+Similarly, quasiliterals are supported in JSON syntax.
 .meIP #H(() >> ( k0 << v0 ) >> ( k1 << v1 ) ...)
 Hash quasiliteral syntax is translated according to the
 .mono
-- 
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