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Perl is worse!

Karl Ulbrich kulbrich at yahoo.com
Fri Jul 28 19:29:52 EDT 2000 
>    A variable gets its type upon assignment.  That is implicit typing.

Variables do not have type.  Data has types.  If a variable later
points to an object of a different type, then calculations using this
variable have a different type to contend with.  

If variables became typed upon assignment, the following would fail:

	a = 1
	a = "z"

> >Huh? Where in Python did you find your declarations? I'm confused.
> 
> a = None
> int(a)
> 
>     a is declared as None at assignment.

Not declared as.  _Refers_ to None.  

> >Well, because it doesn't really make a lot of sense if you want to convert
> >something to an integer when Python can't figure it out. If you're so
> >sure of yourself, you can always do:
> >
> >try:
> >   a = int(b)
> >except ValueError:
> >   a = 0
> 
>     Right, which is basically what I had to do except I left None as None.
> Just seems like a pain in the butt to do after I have allready made sure,
> beyond all doubt, that those variables contain numbers in the first place.

If they already contained numbers (well, strings of digits), and you were
certain, then simply:

	a = int(b)

>     A regex could return a string or None, only one of which is convertable to
> int.  You must litter your code with such checks.

If you do this a *lot*, maybe a little code around re to return digits as
numbers, and None as 0, would be appropriate in that case?


Karl Ulbrich
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