===================================================================
RCS file: /home/cvs/OpenXM_contrib2/asir2000/builtin/strobj.c,v
retrieving revision 1.41
retrieving revision 1.43
diff -u -p -r1.41 -r1.43
--- OpenXM_contrib2/asir2000/builtin/strobj.c	2004/03/12 02:06:48	1.41
+++ OpenXM_contrib2/asir2000/builtin/strobj.c	2004/03/15 06:44:50	1.43
@@ -45,7 +45,7 @@
  * DEVELOPER SHALL HAVE NO LIABILITY IN CONNECTION WITH THE USE,
  * PERFORMANCE OR NON-PERFORMANCE OF THE SOFTWARE.
  *
- * $OpenXM: OpenXM_contrib2/asir2000/builtin/strobj.c,v 1.40 2004/03/11 07:40:41 noro Exp $
+ * $OpenXM: OpenXM_contrib2/asir2000/builtin/strobj.c,v 1.42 2004/03/12 02:15:23 noro Exp $
 */
 #include "ca.h"
 #include "parse.h"
@@ -336,7 +336,10 @@ int register_conv_rule(Obj arg)
 
 int register_conv_func(Obj arg)
 {
-	if ( OID(arg) == O_P && (int)(VR((P)arg))->attr == V_SR ) {
+	if ( !arg ) {
+		convfunc = 0;
+		return 1;
+	} else if ( OID(arg) == O_P && (int)(VR((P)arg))->attr == V_SR ) {
 		convfunc = (FUNC)(VR((P)arg)->priv);
 		/* f must be a function which takes single argument */
 		return 1;
@@ -410,8 +413,10 @@ void Pquotetotex_env(NODE arg,Obj *rp)
 		*rp = (Obj)l;
 	} else if ( ac == 1 && !ARG0(arg) ) {
 		/* set to default */
-		for ( i = 0; qtot_env[i].name; i++ )
+		for ( i = 0; qtot_env[i].name; i++ ) {
+			(qtot_env[i].reg)(0);
 			qtot_env[i].value = 0;
+		}
 		*rp = 0;
 	} else if ( ac == 1 || ac == 2 ) {
 		asir_assert(ARG0(arg),O_STR,"quotetotex_env");
@@ -1086,7 +1091,7 @@ void fnodetotex_tb(FNODE f,TB tb)
 		case I_FORMULA:
 			obj = (Obj)FA0(f);
 			if ( !obj )
-				opname = "0";
+				write_tb("0",tb);
 			else if ( OID(obj) == O_N && NID(obj) == N_C ) {
 				cplx = (C)obj;
 				write_tb("(",tb);