Classes and global statements

[Sheldon]

Scott David Daniels skrev:

> Sheldon wrote:
> > Hi,
> >
> > I have a series of classes that are all within the same file. Each is
> > called at different times by the main script. Now I have discovered
> > that I need several variables returned to the main script. Simple,
> > right? I thought so and simply returned the variables in a tuple:
> > (a,b,c,d,e) = obj.method()
> > Now I keep getting this error: "ValueError: unpack tuple of wrong size"
> What you need to do at this point is read the _whole_ error message
> (including the ugly traceback stuff).  Think hard about what is going
> on.  "ValueError: unpack tuple of wrong size" comes from returning
> a tuple of a different size than your assignment is producing:
>
>      def triple(v):
>          return v, v*v
>
>      x, y, z = triple(13)
>
> Break up the assignment and insert prints:
>
>      # x, y, z = triple(13)
>      temp = triple(13)
>      print "I'm going to expand the triple:", temp
>      x, y, z = temp
>
>
> >  I think this is because I am trying to return some Numeric arrays as
> > well as list and I didn't declare these prior to calling the class
> > method.
> Don't guess and hypothesize; create experiments and test.  Your
> reasoning is off in the ozone.  You waste a lot of time creating
> great theories; make tiny theories and _test_ them.
>
> <<and the theories wander farther and farther off into the weeds>>
>
> --Scott David Daniels
> scott.daniels at acm.org



Thanks for sound advice!
Will give it another go.

/Sheldon