del an imported Class at EOF... why?
tjreedy at udel.edu
Thu Oct 8 22:20:30 CEST 2009
Terry Reedy wrote:
> Hans Mulder wrote:
>> Errrhm, no. He is not deleting the PyQt4 module from sys.modules;
>> he's only deleting the name QtGui from his own namespace. Next
>> time Python comes across
>> from PyQt4 import QtGui
>> , it finds that the module PyQt4 already exists in sys.modules, so
>> Python does not have to load the module again. All it has to do is
>> bind name QtGui in the importing module to the class with the same
>> name in the PyQt4 module. That does not take many cycles.
> I recently discovered that when IDLE restarts (as when one runs a file
> from an edit window), it clears the global namespace but does not clear
> sys.modules. Hence re-running a script that does time-consuming imports
> is much faster, as only the global name binding is done after the first
Whoops, on rechecking, above does not seem to be true. The faster rerun
time I was seeing was due to some other cause. Sorry for the noise.
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