From 8a7a2c372351a9e1da5a907b65887552136a3f53 Mon Sep 17 00:00:00 2001
From: Thomas Kluyver <takowl@gmail.com>
Date: Thu, 13 Oct 2011 16:56:48 +0100
Subject: [PATCH 1/2] Add columns to IPython tab completions of DataFrame
 attributes.

---
 pandas/core/frame.py     | 19 +++++++++++++++++--
 pandas/util/py3compat.py | 11 +++++++++++
 2 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 0efdcd838bf63..934dfb04b8ec1 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -15,6 +15,7 @@
 from StringIO import StringIO
 import csv
 import operator
+import sys
 import warnings
 
 from numpy import nan
@@ -550,7 +551,6 @@ def to_string(self, buf=None, columns=None, colSpace=None,
                   nanRep='NaN', formatters=None, float_format=None,
                   sparsify=True):
         from pandas.core.common import _format, adjoin
-        import sys
 
         if buf is None:  # pragma: no cover
             buf = sys.stdout
@@ -629,7 +629,6 @@ def info(self, verbose=True, buf=None):
             If False, don't print column count summary
         buf : writable buffer, defaults to sys.stdout
         """
-        import sys
         if buf is None:  # pragma: no cover
             buf = sys.stdout
 
@@ -3304,6 +3303,22 @@ def _homogenize(data, index, columns, dtype=None):
 def _put_str(s, space):
     return ('%s' % s)[:space].ljust(space)
 
+def install_ipython_completers():
+    """Register the DataFrame type with IPython's tab completion machinery, so
+    that it knows about accessing column names as attributes."""
+    from IPython.utils.generics import complete_object
+    
+    @complete_object.when_type(DataFrame)
+    def complete_dataframe(obj, prev_completions):
+        return prev_completions + [c for c in obj.columns \
+                                                if py3compat.isidentifier(c)]
+
+# Importing IPython brings in about 200 modules, so we want to avoid it unless
+# we're in IPython (when those modules are loaded anyway).
+if "IPython" in sys.modules:
+    install_ipython_completers()
+
+
 if __name__ == '__main__':
     import nose
     nose.runmodule(argv=[__file__, '-vvs', '-x', '--pdb', '--pdb-failure'],
diff --git a/pandas/util/py3compat.py b/pandas/util/py3compat.py
index e8bb212e215f2..afb48ef41cc95 100644
--- a/pandas/util/py3compat.py
+++ b/pandas/util/py3compat.py
@@ -1,3 +1,14 @@
 import sys
 
 PY3 = (sys.version_info[0] >= 3)
+
+if PY3:
+    def isidentifier(s):
+        return s.isidentifier()
+
+else:
+    # Python 2
+    import re
+    _name_re = re.compile(r"[a-zA-Z_][a-zA-Z0-9_]*$")
+    def isidentifier(s, dotted=False):
+        return bool(_name_re.match(s))

From 07f5324191db789abf8e376726efdc03368619d5 Mon Sep 17 00:00:00 2001
From: Thomas Kluyver <takowl@gmail.com>
Date: Thu, 13 Oct 2011 21:22:44 +0100
Subject: [PATCH 2/2] Catch and silence errors in installing IPython
 completers.

Avoid problems with older versions of IPython (pre 0.11)

Closes gh-230
---
 pandas/core/frame.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/pandas/core/frame.py b/pandas/core/frame.py
index 934dfb04b8ec1..90ae7feb15d83 100644
--- a/pandas/core/frame.py
+++ b/pandas/core/frame.py
@@ -3316,7 +3316,10 @@ def complete_dataframe(obj, prev_completions):
 # Importing IPython brings in about 200 modules, so we want to avoid it unless
 # we're in IPython (when those modules are loaded anyway).
 if "IPython" in sys.modules:
-    install_ipython_completers()
+    try:
+        install_ipython_completers()
+    except Exception:
+        pass
 
 
 if __name__ == '__main__':