From 40880f748e5f0dbe6318b9953d6eae998d9c1458 Mon Sep 17 00:00:00 2001
From: Jan Wielemaker <J.Wielemaker@vu.nl>
Date: Sun, 28 Feb 2021 17:09:45 +0100
Subject: [PATCH] PORT: Support new style SWI-Prolog neck syntax from the core
 highlight module and support the

---
 lib/highlight.pl                        | 11 ++++++-----
 web/js/codemirror/mode/prolog/prolog.js |  2 +-
 2 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/lib/highlight.pl b/lib/highlight.pl
index c2a69194d..27946b997 100644
--- a/lib/highlight.pl
+++ b/lib/highlight.pl
@@ -884,11 +884,12 @@
 style(table_option(_Mode), table_option,		   [text]).
 
 
-neck_text(clause,       (:-)).
-neck_text(grammar_rule, (-->)).
-neck_text(method(send), (:->)).
-neck_text(method(get),  (:<-)).
-neck_text(directive,    (:-)).
+neck_text(clause,       (:-))  :- !.
+neck_text(grammar_rule, (-->)) :- !.
+neck_text(method(send), (:->)) :- !.
+neck_text(method(get),  (:<-)) :- !.
+neck_text(directive,    (:-))  :- !.
+neck_text(Text,         Text).		% new style
 
 head_type(exported,	 head_exported).
 head_type(public(_),	 head_public).
diff --git a/web/js/codemirror/mode/prolog/prolog.js b/web/js/codemirror/mode/prolog/prolog.js
index 41db8c15c..cabcef6a1 100644
--- a/web/js/codemirror/mode/prolog/prolog.js
+++ b/web/js/codemirror/mode/prolog/prolog.js
@@ -40,7 +40,7 @@
 
   var isSymbolChar = /[-#$&*+./:<=>?@\\^~]/;	/* Prolog glueing symbols chars */
   var isSoloChar   = /[[\]{}(),;|!]/;		/* Prolog solo chars */
-  var isNeck       = /^(:-|-->)$/;
+  var isNeck       = /^(:-|-->|=>)$/;
   var isControlOp  = /^(,|;|->|\*->|\\+|\|)$/;