From 99dc21b67a895dc10d3c846bc158d27c839cee48 Mon Sep 17 00:00:00 2001
From: Chris Angelico <rosuav@gmail.com>
Date: Thu, 12 Jun 2014 02:18:54 +1000
Subject: [PATCH] Optimize as per TODO (thanks Damien!)

---
 py/objstr.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/py/objstr.c b/py/objstr.c
index 456f5fe801..b219be6d35 100644
--- a/py/objstr.c
+++ b/py/objstr.c
@@ -457,8 +457,7 @@ STATIC mp_obj_t str_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
                 pstop = (const char *)self_data + self_len;
             }
             if (pstop < pstart) {
-                // TODO (optimization): Return a hard-coded "" for this.
-                pstop = pstart;
+                return MP_OBJ_NEW_QSTR(MP_QSTR_);
             }
             return mp_obj_new_str_of_type(type, (const byte *)pstart, pstop - pstart);
         }