1. variables in Py
- Posted by Jerry Story <jstory at FREENET.EDMONTON.AB.CA>
Oct 21, 2000
-
Last edited Oct 22, 2000
David Cuny,
The py.txt says variables are created by assigning a value to it.
Is this good enough?
Suppose I create a variable like so:
number = 0 -- The variable 'number' is created
Then suppose in another place I want to re-initialize 'number', and I
make a typo:
numer = 0 -- Another variable is created, by a typo.
In a normal language, this is caught instantly as "undeclared" and I can
fix it instantly.
I used to program in GFA Basic. It did not have explicit declarations of
global variables, and consequently simple typos tended to cause major
trials and tribulations.
Jerry Story
2. Re: variables in Py
- Posted by David Cuny <dcuny at LANSET.COM>
Oct 21, 2000
-
Last edited Oct 22, 2000
Jerry Story wrote:
> number = 0 -- The variable 'number' is created
> ...
> numer = 0 -- Another variable is created, by a typo.
>
> In a normal language, this is caught instantly as "undeclared" and I can
> fix it instantly.
'normal' language. heh.
I've used QBasic, and suffered from the same sort of problems that you are
alluding to.
No language is foolproof, and the method that Py uses (in this case, taken
directly from Python) isn't as 'safe' as the one Euphoria uses. It also
fails to enforce the datatype of a variable.
But I think that, in this case, it offers a reasonable level of safety. Get
back to me in a couple of months, and I could have a different opinion. But
it's worth trying out.
> I used to program in GFA Basic. It did not have explicit
> declarations of global variables, and consequently simple
> typos tended to cause major trials and tribulations.
The use of namespaces in Py greatly reduces the problems with global
variables.
Thanks for the feedback!
-- David Cuny
