Remove unnecessary metaclass and allow registration of magic classes.

This lets us register uninstantiated magic classes as well, making the
init logic a bit cleaner in the main shell class.

IPython/core/interactiveshell.py

@@ -1999,12 +1999,10 b' class InteractiveShell(SingletonConfigurable):'
                                    user_magics=mf.UserMagics(self))
         self.configurables.append(self.magics_manager)
 
-        all_m = [t(self) for t in [mf.BasicMagics, mf.CodeMagics,
+        self.magics_manager.register(mf.BasicMagics, mf.CodeMagics,
              mf.ConfigMagics, mf.NamespaceMagics, mf.ExecutionMagics,
              mf.AutoMagics, mf.OSMagics, mf.LoggingMagics, mf.ExtensionsMagics,
-             mf.PylabMagics, mf.DeprecatedMagics] ]
-        self.all_m = all_m
-        self.magics_manager.register(*all_m)
+             mf.PylabMagics, mf.DeprecatedMagics)
 
         # FIXME: Move the color initialization to the DisplayHook, which
         # should be split into a prompt manager and displayhook. We probably

IPython/core/magic.py

@@ -178,6 +178,10 b' class MagicsManager(Configurable):'
             if not m.registered:
                 raise ValueError("Class of magics %r was constructed without "
                                  "the @register_macics class decorator")
+            if type(m) is type:
+                # If we're given an uninstantiated class
+                m = m(self.shell)
+
             for mtype in magic_types:
                 self.magics[mtype].update(m.magics[mtype])
 
@@ -228,10 +232,7 b' class Magics(object):'
     # Non-configurable class attributes
     magics = Dict
 
-    class __metaclass__(type):
-        def __new__(cls, name, bases, dct):
-            cls.registered = False
-            return type.__new__(cls, name, bases, dct)
+    registered = False
 
     def __init__(self, shell):
         if not(self.__class__.registered):
@@ -241,7 +242,8 b' class Magics(object):'
         for mtype in magic_types:
             tab = mtab[mtype]
             for magic_name, meth_name in self.magics[mtype].iteritems():
-                tab[magic_name] = getattr(self, meth_name)
+                if isinstance(meth_name, basestring):
+                    tab[magic_name] = getattr(self, meth_name)
         self.magics.update(mtab)
 
     def arg_err(self,func):

IPython/core/magic_functions.py

@@ -143,7 +143,6 b' class BasicMagics(Magics):'
                     magic_docs.append('%s%s:\n\t%s\n' %
                                       (escape, fname, fndoc))
 
-
         magic_docs = ''.join(magic_docs)
 
         if mode == 'rest':