diff --git a/gui_status.c b/gui_status.c
index 0790e84..f59d3fd 100644
--- a/gui_status.c
+++ b/gui_status.c
@@ -615,16 +615,44 @@ static struct edit_ops edit_ops_expr = {
 };
 
 
-static void edit_any_expr(GtkWidget *widget, struct expr **expr,
-    const char *tooltip)
+void edit_expr(struct expr **expr, const char *tooltip)
 {
-	setup_edit(widget, &edit_ops_expr, expr, tooltip);
+	setup_edit(status_entry, &edit_ops_expr, expr, tooltip);
 }
 
 
-void edit_expr(struct expr **expr, const char *tooltip)
+/* ----- distance expressions ---------------------------------------------- */
+
+
+static void dist_expr_store(const char *s, void *ctx)
 {
-	edit_any_expr(status_entry, expr, tooltip);
+	struct expr **anchor = ctx;
+	struct expr *expr;
+
+	expr_store(s, ctx);
+	expr = *anchor;
+	if (expr->op == op_num && !expr->u.num.exponent && !expr->u.num.n)
+		expr->u.num.exponent = 1;
+}
+
+
+static struct edit_ops edit_ops_dist_expr = {
+	.retrieve	= expr_retrieve,
+	.status		= expr_status,
+	.store		= dist_expr_store,
+};
+
+
+static void edit_any_dist_expr(GtkWidget *widget, struct expr **expr,
+    const char *tooltip)
+{
+	setup_edit(widget, &edit_ops_dist_expr, expr, tooltip);
+}
+
+
+void edit_dist_expr(struct expr **expr, const char *tooltip)
+{
+	edit_any_dist_expr(status_entry, expr, tooltip);
 }
 
 
@@ -633,13 +661,13 @@ void edit_x(struct expr **expr, const char *tooltip)
 	vacate_widget(status_box_x);
 	gtk_container_add(GTK_CONTAINER(status_box_x), status_entry_x);
 	gtk_widget_show(status_box_x);
-	edit_any_expr(status_entry_x, expr, tooltip);
+	edit_any_dist_expr(status_entry_x, expr, tooltip);
 }
 
 
 void edit_y(struct expr **expr, const char *tooltip)
 {
-	edit_any_expr(status_entry_y, expr, tooltip);
+	edit_any_dist_expr(status_entry_y, expr, tooltip);
 }
 
 
diff --git a/gui_status.h b/gui_status.h
index 82af96a..52dde22 100644
--- a/gui_status.h
+++ b/gui_status.h
@@ -47,6 +47,7 @@ void edit_expr(struct expr **expr, const char *tooltip);
 void edit_expr_list(struct expr *expr,
     void (*set_values)(void *user, const struct value *values, int n_values),
     void *user, const char *tooltip);
+void edit_dist_expr(struct expr **expr, const char *tooltip);
 void edit_x(struct expr **expr, const char *tooltip);
 void edit_y(struct expr **expr, const char *tooltip);
 void edit_nothing(void);
diff --git a/inst.c b/inst.c
index 1572b76..b9dee56 100644
--- a/inst.c
+++ b/inst.c
@@ -754,7 +754,7 @@ int inst_vec(struct vec *vec, struct coord base)
 
 static void obj_line_edit(struct obj *obj)
 {
-	edit_expr(&obj->u.line.width, "Line width");
+	edit_dist_expr(&obj->u.line.width, "Line width");
 }
 
 
@@ -805,7 +805,7 @@ int inst_line(struct obj *obj, struct coord a, struct coord b, unit_type width)
 
 static void obj_rect_edit(struct obj *obj)
 {
-	edit_expr(&obj->u.rect.width, "Line width");
+	edit_dist_expr(&obj->u.rect.width, "Line width");
 }
 
 
@@ -934,7 +934,7 @@ int inst_pad(struct obj *obj, const char *name, struct coord a, struct coord b)
 
 static void obj_arc_edit(struct obj *obj)
 {
-	edit_expr(&obj->u.arc.width, "Line width");
+	edit_dist_expr(&obj->u.arc.width, "Line width");
 }
 
 
@@ -1008,7 +1008,7 @@ int inst_arc(struct obj *obj, struct coord center, struct coord start,
 
 static void obj_meas_edit(struct obj *obj)
 {
-	edit_expr(&obj->u.meas.offset, "Measurement line offset");
+	edit_dist_expr(&obj->u.meas.offset, "Measurement line offset");
 }