From bf40154ff1c94ceb71153922a446c3150d9f8381 Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Mon, 27 Sep 2010 22:31:06 +0100
Subject: [PATCH] fix UN #189 and #172

---
 pl/messages.yap |   4 +-
 pl/utils.yap    | 131 +++++++++++++++++++++++++++---------------------
 2 files changed, 75 insertions(+), 60 deletions(-)

diff --git a/pl/messages.yap b/pl/messages.yap
index 8a71829b6..611206611 100644
--- a/pl/messages.yap
+++ b/pl/messages.yap
@@ -222,8 +222,8 @@ system_message(error(permission_error(modify,dynamic_procedure,_), Where)) -->
 	[ 'PERMISSION ERROR- ~w: modifying a dynamic procedure' - [Where] ].
 system_message(error(permission_error(modify,flag,W), _)) -->
 	[ 'PERMISSION ERROR- cannot modify flag ~w' - [W] ].
-system_message(error(permission_error(modify,operator,W), _)) -->
-	[ 'PERMISSION ERROR- T cannot declare ~w an operator' - [W] ].
+system_message(error(permission_error(modify,operator,W), Q)) -->
+	[ 'PERMISSION ERROR- ~w: cannot modify operator ~q' - [Q,W] ].
 system_message(error(permission_error(modify,dynamic_procedure,F), Where)) -->
 	[ 'PERMISSION ERROR- ~w: modifying dynamic procedure ~w' - [Where,F] ].
 system_message(error(permission_error(modify,static_procedure,F), Where)) -->
diff --git a/pl/utils.yap b/pl/utils.yap
index 7ceb01e24..816515f73 100644
--- a/pl/utils.yap
+++ b/pl/utils.yap
@@ -1,65 +1,80 @@
-/*************************************************************************
-*									 *
-*	 YAP Prolog 							 *
-*									 *
-*	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
-*									 *
-* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997	 *
-*									 *
-**************************************************************************
-*									 *
-* File:		utils.yap						 *
-* Last rev:	8/2/88							 *
-* mods:									 *
-* comments:	Some utility predicates available in yap		 *
-*									 *
-*************************************************************************/
+ /*************************************************************************
+ *									 *
+ *	 YAP Prolog 							 *
+ *									 *
+ *	Yap Prolog was developed at NCCUP - Universidade do Porto	 *
+ *									 *
+ * Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997	 *
+ *									 *
+ **************************************************************************
+ *									 *
+ * File:		utils.yap						 *
+ * Last rev:	8/2/88							 *
+ * mods:									 *
+ * comments:	Some utility predicates available in yap		 *
+ *									 *
+ *************************************************************************/
 
-op(P,T,V) :-
-	'$check_op'(P,T,V,op(P,T,V)),
-	'$op'(P, T, V).
+ op(P,T,V) :-
+	 '$check_op'(P,T,V,op(P,T,V)),
+	 '$op'(P, T, V).
 
-'$check_op'(P,T,V,G) :-
-	(
-	 var(P) ->
-	 '$do_error'(instantiation_error,G)
-	;
-	 var(T) ->
-	 '$do_error'(instantiation_error,G)
-	;
-	 var(V) ->
-	 '$do_error'(instantiation_error,G)
-	;
-	 \+ integer(P) ->
-	 '$do_error'(type_error(integer,P),G)
-	;
-	 \+ atom(T) ->
-	 '$do_error'(type_error(atom,T),G)
-	;
-	 P < 0 ->
-	 '$do_error'(domain_error(operator_priority,P),G)
-	;
-	 P > 1200 ->
-	 '$do_error'(domain_error(operator_priority,P),G)
-	;
-	 \+ '$associativity'(T) ->
-	 '$do_error'(domain_error(operator_specifier,T),G)
-	;
-	 '$check_op_name'(V,G)
-	).
+ '$check_op'(P,T,V,G) :-
+	 (
+	  var(P) ->
+	  '$do_error'(instantiation_error,G)
+	 ;
+	  var(T) ->
+	  '$do_error'(instantiation_error,G)
+	 ;
+	  var(V) ->
+	  '$do_error'(instantiation_error,G)
+	 ;
+	  \+ integer(P) ->
+	  '$do_error'(type_error(integer,P),G)
+	 ;
+	  \+ atom(T) ->
+	  '$do_error'(type_error(atom,T),G)
+	 ;
+	  P < 0 ->
+	  '$do_error'(domain_error(operator_priority,P),G)
+	 ;
+	  P > 1200 ->
+	  '$do_error'(domain_error(operator_priority,P),G)
+	 ;
+	  \+ '$associativity'(T) ->
+	  '$do_error'(domain_error(operator_specifier,T),G)
+	 ;
+	  '$check_op_name'(V,G)
+	 ).
 
-'$associativity'(xfx).
-'$associativity'(xfy).
-'$associativity'(yfx).
-'$associativity'(yfy).
-'$associativity'(xf).
-'$associativity'(yf).
-'$associativity'(fx).
-'$associativity'(fy).
+ '$associativity'(xfx).
+ '$associativity'(xfy).
+ '$associativity'(yfx).
+ '$associativity'(yfy).
+ '$associativity'(xf).
+ '$associativity'(yf).
+ '$associativity'(fx).
+ '$associativity'(fy).
 
-'$check_op_name'(V,G) :-
-	 var(V), !,
-	 '$do_error'(instantiation_error,G).
+ '$check_op_name'(V,G) :-
+	  var(V), !,
+	  '$do_error'(instantiation_error,G).
+ '$check_op_name'(',',G) :- !,
+	  '$do_error'(permission_error(modify,operator,','),G).
+ '$check_op_name'('[]',G) :- !,
+	  '$do_error'(permission_error(create,operator,'[]'),G).
+ '$check_op_name'('{}',G) :- !,
+	  '$do_error'(permission_error(create,operator,'{}'),G).
+ '$check_op_name'('|',G) :- !,
+	 G = op(P, T, _),
+	 (
+	  integer(P),
+	  P < 1001
+	 ;
+	  Fix \== xfx, Fix \== xfy, Fix \== yfx, Fix \== yfy
+	 ),
+	 '$do_error'(permission_error(create,operator,'|'),G).
 '$check_op_name'(V,_) :-
 	 atom(V), !.
 '$check_op_name'(M:A, G) :-