Merge pull request #8430 from Lucretiel/patch-1

register now checks for missing ctypes

IPython/lib/inputhook.py

@@ -107,7 +107,7 b' class InputHookManager(object):'
     def __init__(self):
         if ctypes is None:
             warn("IPython GUI event loop requires ctypes, %gui will not be available")
-            return
+        else:
         self.PYFUNC = ctypes.PYFUNCTYPE(ctypes.c_int)
         self.guihooks = {}
         self.aliases = {}
@@ -197,6 +197,7 b' class InputHookManager(object):'
                     ...
         """
         def decorator(cls):
+            if ctypes is not None:
             inst = cls(self)
             self.guihooks[toolkitname] = inst
             for a in aliases: