Extensions no longer responsible for checking if they are already loaded

IPython/extensions/autoreload.py

@@ -516,7 +516,6 b' class AutoreloadMagics(Magics):'
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
-    if 'autoreload' not in ip.extension_manager.loaded:
-        auto_reload = AutoreloadMagics(ip)
-        ip.register_magics(auto_reload)
-        ip.set_hook('pre_run_code_hook', auto_reload.pre_run_code_hook)
+    auto_reload = AutoreloadMagics(ip)
+    ip.register_magics(auto_reload)
+    ip.set_hook('pre_run_code_hook', auto_reload.pre_run_code_hook)

IPython/extensions/cythonmagic.py

@@ -276,5 +276,4 b' class CythonMagics(Magics):'
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
-    if 'cythonmagic' not in ip.extension_manager.loaded:
-        ip.register_magics(CythonMagics)
+    ip.register_magics(CythonMagics)

IPython/extensions/octavemagic.py

@@ -364,5 +364,4 b' __doc__ = __doc__.format('
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
-    if 'octavemagic' not in ip.extension_manager.loaded:
-        ip.register_magics(OctaveMagics)
+    ip.register_magics(OctaveMagics)

IPython/extensions/rmagic.py

@@ -590,5 +590,4 b' __doc__ = __doc__.format('
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
-    if 'rmagic' not in ip.extension_manager.loaded:
-        ip.register_magics(RMagics)
+    ip.register_magics(RMagics)

IPython/extensions/storemagic.py

@@ -211,5 +211,4 b' class StoreMagics(Magics):'
 
 def load_ipython_extension(ip):
     """Load the extension in IPython."""
-    if 'storemagic' not in ip.extension_manager.loaded:
-        ip.register_magics(StoreMagics)
+    ip.register_magics(StoreMagics)