del an imported Class at EOF... why?
Terry Reedy
tjreedy at udel.edu
Thu Oct 8 01:42:59 EDT 2009
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 run.
More information about the Python-list
mailing list