Arguments and attributes with the same name

[Steven Schveighoffer]

On Thu, 04 Mar 2010 11:49:13 -0500, bearophile <bearophileHUGS at lycos.com>  
wrote:

> Steven Schveighoffer:
>> I think the point is, the statement x = x + 1; isn't any more or less
>> ambiguous in D than it is in python.  There is a well-defined meaning  
>> (and
>> in fact the same meaning).
>
> It's not the same meaning, this program prints "1":
>
> import std.c.stdio: printf;
> class Foo {
>     int x;
>     this() {}
>     void foo() {
>         x = x + 1;
>     }
> }
> void main() {
>     Foo f = new Foo();
>     f.foo();
>     printf("%d\n", f.x); // prints 1
> }
>
> An equivalent Python program with "x = x + 1;" prints:
> UnboundLocalError: local variable 'x' referenced before assignment
> Because the usage of "self." is obligatory.

That's not the ambiguity being discussed.  What is being discussed is when  
there is a local parameter with the same name as an instance field.  In  
that context, (at least from what I read in this thread) D and python are  
the same.

Anyway, it's not important.  I agree that it may be good to disallow this  
 from happening in the first place.

-Steve