From 71b02e3044d1a686a58f895d8a0431104b2c1d45 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A1ssio=20Botaro?= <cassiobotaro@gmail.com>
Date: Sun, 3 May 2015 13:35:05 -0300
Subject: [PATCH 1/4] Maintain backward compatibility

Little change to maintain backward compatibility, related to #590
---
 gluon/storage.py | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/gluon/storage.py b/gluon/storage.py
index 3b0780fd..117ccac1 100644
--- a/gluon/storage.py
+++ b/gluon/storage.py
@@ -275,7 +275,7 @@ class List(list):
     instead of `IndexOutOfBounds`.
     """
 
-    def __call__(self, i, default=None, cast=None, otherwise=None):
+    def __call__(self, i, default=DEFAULT, cast=None, otherwise=None):
         """Allows to use a special syntax for fast-check of `request.args()`
         validity
         Args:
@@ -291,7 +291,9 @@ class List(list):
                 request.args(0,default=0,cast=int,otherwise='http://error_url')
                 request.args(0,default=0,cast=int,otherwise=lambda:...)
         """
-        value = self[i] or default
+        value = self[i]
+        if not value and default is not DEFAULT:
+            value, cast = default, False
         try:
             if cast:
                 value = cast(value)

From ccc4b96709edef936f29cf51c2b199fda1b93e6d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A1ssio=20Botaro?= <cassiobotaro@gmail.com>
Date: Sun, 3 May 2015 13:36:24 -0300
Subject: [PATCH 2/4] Added one more test

Added one more test to avoid mistake with backward compatibility
---
 gluon/tests/test_storage.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/gluon/tests/test_storage.py b/gluon/tests/test_storage.py
index 804a3fb8..328f1e09 100644
--- a/gluon/tests/test_storage.py
+++ b/gluon/tests/test_storage.py
@@ -138,6 +138,8 @@ class TestList(unittest.TestCase):
         self.assertEqual(a(3, cast=int), 1234)
         a.append('x')
         self.assertRaises(HTTP, a, 4, cast=int)
+        b = List()
+        self.assertEqual(b(0, cast=int, default=None), None)
 
 
 if __name__ == '__main__':

From f6db7c995f162c50b20b7cf857b543c37f5d3848 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A1ssio=20Botaro?= <cassiobotaro@gmail.com>
Date: Sun, 3 May 2015 14:02:11 -0300
Subject: [PATCH 3/4] Its necessary because of default=None trick

---
 gluon/storage.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gluon/storage.py b/gluon/storage.py
index 117ccac1..4a1e46a7 100644
--- a/gluon/storage.py
+++ b/gluon/storage.py
@@ -293,7 +293,7 @@ class List(list):
         """
         value = self[i]
         if not value and default is not DEFAULT:
-            value, cast = default, False
+            value, cast, otherwise = default, False, False
         try:
             if cast:
                 value = cast(value)

From c36c39178610867330ebf1927a2a3edeb7dcb35e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A1ssio=20Botaro?= <cassiobotaro@gmail.com>
Date: Sun, 3 May 2015 14:03:26 -0300
Subject: [PATCH 4/4] More test to prove backward compatibility

---
 gluon/tests/test_storage.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/gluon/tests/test_storage.py b/gluon/tests/test_storage.py
index 328f1e09..e518e4d2 100644
--- a/gluon/tests/test_storage.py
+++ b/gluon/tests/test_storage.py
@@ -140,6 +140,7 @@ class TestList(unittest.TestCase):
         self.assertRaises(HTTP, a, 4, cast=int)
         b = List()
         self.assertEqual(b(0, cast=int, default=None), None)
+        self.assertEqual(b(0, cast=int, default=None, otherwise='something'), None)
 
 
 if __name__ == '__main__':