The programming style imposed by PyQt (and other GUI toolkit wrappers) is to create an application instance with some widgets and to enter into an event loop that locks you from the Python command line interpreter.
Module iqt enables you to:
Module iqt works by hooking qApp->processEvents() on the event hook of the readline module. The GNU readline library closes the event loop by calling qApp->processEvent() at a maximum rate of 10 times per second while reading your keyboard input.
To see how iqt works, play with ICompass.py by running
python -i ICompass.py
python ICompass.py
ipython ICompass.py
This behavior impairs the usefulness of the module rlcompleter. The classes in PyQwt offer a method getLazyNames() as an alternative to be used in combination with the modules iqt.rlcompleter and iqt.FlexCompleter instead of rlcompleter in the standard Python library and IPython.FlexCompleter.
Full support for the builtin function dir() is present in sip-3.7; in this case the standard readline completers will work.