From 920beabd30116f379d0be2806940f24e17dd9a32 2012-02-11 22:08:30
From: Min RK <benjaminrk@gmail.com>
Date: 2012-02-11 22:08:30
Subject: [PATCH] Merge pull request #1396 from takluyver/magic_tb_fix

In order for the %tb magic to work as expected, no other error can be raised by invoking it. Even if an error is caught immediately, it affects the 'last error' values in sys.

This cuts a try/except block out of ip.magic(). Happily, in this case there was a simpler way to do the same thing using `str.partition`

---

diff --git a/IPython/core/interactiveshell.py b/IPython/core/interactiveshell.py
index a1bd92f..8ea90d7 100644
--- a/IPython/core/interactiveshell.py
+++ b/IPython/core/interactiveshell.py
@@ -2005,14 +2005,9 @@ class InteractiveShell(SingletonConfigurable, Magic):
         if next_input:
             self.set_next_input(next_input)
 
-        args = arg_s.split(' ',1)
-        magic_name = args[0]
+        magic_name, _, magic_args = arg_s.partition(' ')
         magic_name = magic_name.lstrip(prefilter.ESC_MAGIC)
 
-        try:
-            magic_args = args[1]
-        except IndexError:
-            magic_args = ''
         fn = getattr(self,'magic_'+magic_name,None)
         if fn is None:
             error("Magic function `%s` not found." % magic_name)