do not attempt custom completers on empty line

IPython/completer.py

@@ -531,6 +531,8 b' class IPCompleter(Completer):'
 
     def dispatch_custom_completer(self,text):
         # print "Custom! '%s' %s" % (text, self.custom_completers) # dbg
+        if not text.strip():
+            return None
         line = self.lbuf
         event = Struct()
         event.line = line

IPython/iplib.py

@@ -6,7 +6,7 b' Requires Python 2.3 or newer.'
 
 This file contains all the classes and helper functions specific to IPython.
 
-$Id: iplib.py 1854 2006-10-30 19:54:25Z vivainio $
+$Id: iplib.py 1859 2006-11-02 06:39:54Z vivainio $
 """
 
 #*****************************************************************************
@@ -1650,6 +1650,7 b' want to merge them back into the new files.""" % locals()'
 
                 l2 = self.transform_alias(fn,rest)
                 # dir -> dir 
+                # print "alias",line, "->",l2  #dbg
                 if l2 == line:
                     break
                 # ls -> ls -F should not recurse forever