On Jul 7, 2:33 am, Peter Otten <__pete...@web.de> wrote:
> rocky wrote:
> > Someone recently reported a problem in pydb where a function defined
> > in his program was conflicting with amodulenamethat pydb uses. I
> > think I understand what's wrong, but I don't have any elegant
> > solutions to the problem. Suggestions would be appreciated.
>
> > In a nutshell, here's the problem:
>
> > In file fns:
>
> > def foo(): print "foo"
>
> > In file pdebug.py:
>
> > import fns, sys
>
> > def trace_dispatch(frame, event, arg):
> > fns.foo()
> > print frame, event, arg
> > return trace_dispatch
>
> > sys.settrace(trace_dispatch)
> > execfile('myprogram.py')
>
> > Finally file myprogram.py:
>
> > def fns(): print "This is the *other* fns"
>
> > When you run pdebug.py you get:
>
> > $ python pdebug.py
> > foo
> > <frame object at 0xdd9030> call None
> > foo
> > <frame object at 0xdd9030> line None
> > Traceback (most recent call last):
> > File "pdebug.py", line 7, in <module>
> > execfile('myprogram.py')
> > File "myprogram.py", line 1, in <module>
> > def fns(): print "This is the *other* fns"
> > File "pdebug.py", line 3, in trace_dispatch
> > fns.foo()
> > AttributeError: 'function' object has no attribute 'foo'
>
> > Basically inside the trace hook, local functions are visible and take
> > precedence over (global)modulenames.
I was sloppy here. The "local" is the wrong word as suggested by the
first remedy proposed.
"entry in the global namespace dictionary" is probably closer to the
truth.
> > I could move "import fns"
> > inside trace_dispatch(), but I'd have to do that in all of the methods
> > thatmodule"fns" is used. Also note that using the form:
> > from fns import foo
>
> > would eliminate the conflict on "fns", but I'd still have potential
> > conflicts on "foo". Using more obscure names (e.g. pydb_fns) would
> > reduce the chance of a conflict but not eliminate it.
>
> > Suggestions?
>
> Can you run the program in another namespace?
>
> execfile("myprogram.py", {"__name__":"__main__"})
>
> Alternatively move trace_dispatch into yet anothermoduleand import it into
> pdebug.
>
> from elsewhere import trace_dispatch
>
> Peter
Both of these work. Thanks! (I haven't figured out how to adapt it to
the messier context of the program yet). The second suggestion
interesting/weird:
by putting trace_dispatch in another module, compilation and name/
function resolution of fns.foo
is done before myprogram has a chance to redefine fns.
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