[IPython-dev] Problem when sys.argv does not exist

[Fernando Perez]

Adam Hupp wrote:
> I'm running into a problem embedding when sys.argv is not defined.
> I'm running ipython from a C extension that does not set sys.argv.
> The root of the problem is that DPyGetOpt unconditionally checks the
> passed arguments against sys.argv.  With no sys.argv this raises an
> exception and aborts the whole program.  Checked against 0.5.0.  The
> following change to DPyGetOpt.py should fix it:
> 
> <               if args == sys.argv:
> <                       args = sys.argv[1:]
> ---
> 
>>              if hasattr(sys, "argv"):
>>                      if args == sys.argv:
>>                              args = sys.argv[1:]

Cool!  Ipython _can_ run from within C extensions :)  A while back a user 
asked about it and said he had some problems, but I never heard back from him. 
  So I had no idea whether it worked or not.

I applied your change as:

                 if hasattr(sys, "argv") and args == sys.argv:
                     args = sys.argv[1:]

Given the short-circuiting behavior of 'and', this should be fully equivalent 
to your suggestion and slightly cheaper than a nested 'if'.

Thanks for the contribution, it's already in CVS.

Regards,

Fernando.