From 24021748d20a756206f5df60d958ce6fd0dd8c5c Mon Sep 17 00:00:00 2001
From: Nick Logan <nlogan@gmail.com>
Date: Tue, 8 Sep 2026 07:20:51 -0700
Subject: [PATCH] Fall back to any-args when an expr does not reach the closing
 paren

In `[ <expr>? || <any-args> ]` the first branch always succeeds, so any-
args is only reached by backtracking into the alternation once the ')'
fails. That only works because an alternation followed by whitespace in
a rule is currently not ratcheted, which rakudo may change in the
future. Requiring the ')' after the expr keeps the fallback reachable
either way.
---
 lib/CSS/Grammar/CSS21.rakumod | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/CSS/Grammar/CSS21.rakumod b/lib/CSS/Grammar/CSS21.rakumod
index 0c6a009..0158fd7 100644
--- a/lib/CSS/Grammar/CSS21.rakumod
+++ b/lib/CSS/Grammar/CSS21.rakumod
@@ -93,7 +93,7 @@ rule pseudo:sym<function> {':'[<pseudo-function>||<pseudo-function=.any-pseudo-f
 # assume anything else is a class
 rule pseudo:sym<class>    {':' <class=.Ident><!before '('>}
 
-rule any-function         {<Ident>'(' [ <expr>? || <any-args> ] ')'}
+rule any-function         {<Ident>'(' [ <expr>? <?before ')'> || <any-args> ] ')'}
 
 proto rule pseudo-function {*}
 rule pseudo-function:sym<lang> {:i'lang(' [ <Ident> || <any-args> ] ')'}