better use of blender api

io_mesh_stl/blender_utils.py

@@ -31,12 +31,12 @@ def faces_from_mesh(ob, apply_modifier=False, triangulate=True):
         Split the quad into two triangles
     '''
 
-    if ob.type not in ('MESH', 'CURVE', 'SURFACE', 'META'):
-        return ()
-
     # get the modifiers
-    mesh = ob.create_mesh(bpy.context.scene,
-                          True, "PREVIEW") if apply_modifier else ob.data
+    try:
+        mesh = ob.create_mesh(bpy.context.scene,
+                                apply_modifier, "PREVIEW")
+    except SystemError:
+        return ()
 
     def iter_face_index():
         '''