From de8cbd046c9b83b150d064e8157bd3948a93a3b9 Mon Sep 17 00:00:00 2001
From: uid49918 <uid49918@b08c6af1-5177-4d33-ba66-4b1c6b8b522a>
Date: Wed, 4 Jul 2001 16:45:42 +0000
Subject: [PATCH] fix coroutining and goal expansion

git-svn-id: https://yap.svn.sf.net/svnroot/yap/trunk@115 b08c6af1-5177-4d33-ba66-4b1c6b8b522a
---
 pl/corout.yap | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/pl/corout.yap b/pl/corout.yap
index 2184e48ce..4be3cf56c 100644
--- a/pl/corout.yap
+++ b/pl/corout.yap
@@ -61,7 +61,28 @@
 %'), fail.
 '$wake_up_goal'([Module1|Continuation], LG) :-
 	'$execute_woken_system_goals'(LG),
-	'$execute'(Module1:Continuation).
+	'$do_continuation'(Continuation, Module1).
+
+
+%
+% in the first two cases restore register  immediately and proceed
+% to continuation. In the last case take care with modules, but do
+% not act as if a meta-call.
+% 
+%
+'$do_continuation'('$restore_regs'(X), _) :- !,
+	'$restore_regs'(X).
+'$do_continuation'('$restore_regs'(X,Y), _) :- !,
+	'$restore_regs'(X,Y).
+'$do_continuation'(Continuation, Module1) :-
+	'$mod_switch'(Module1,'$execute_continuation'(Continuation,Module1)).
+
+'$execute_continuation'(Continuation, Module1) :-
+	'$undefined'(Continuation), !,
+        '$undefp'([Module1|Continuation]).
+'$execute_continuation'(Continuation, _) :-
+         % do not do meta-expansion nor any fancy stuff.
+	 '$execute0'(Continuation).
 
 
 '$execute_woken_system_goals'([]).