questions about Exceptions?

[cokofreedom at gmail.com]

> def Calc():
>     global nbr
>     try:
>         print eval(nbr)
>         #a = Label(mygui, text=eval(nbr))
>         #a.place(relx=0.4, rely=0.1, anchor=CENTER)
>     except:
>         print "Not computable"
>     nbr = ""
>
> def Erase():
>     global nbr
>     nbr = ""

Seems to me you could be better off passing a parameter and a return
statement of None (or your parameter cleaned) for those functions,
which should work. Given an input, Eval it and then return None. That
way you wouldn't need the Erase...