'int' is enough for 'length' to migrate code from x86 to x64

[Ary Borenszweig via Digitalmars-d]

On 11/19/14, 7:03 AM, Don wrote:
> On Tuesday, 18 November 2014 at 18:23:52 UTC, Marco Leise wrote:
 >
> Weird consequence: using subtraction with an unsigned type is nearly
> always a bug.
>
> I wish D hadn't called unsigned integers 'uint'. They should have been
> called '__uint' or something. They should look ugly. You need a very,
> very good reason to use an unsigned type.
>
> We have a builtin type that is deadly but seductive.
>

I agree. An array's length makes sense as an unsigned ("an array can't 
have a negative length, right?") but it leads to the bugs you say. For 
example:

~~~
import std.stdio;

void main() {
   auto a = [1, 2, 3];
   auto b = [1, 2, 3, 4];
   if (a.length - b.length > 0) {
     writeln("Can you spot the bug that easily?");
   }
}
~~~

Yes, it makes sense, but at the same time it leads to super unintuitive 
math operations being involved.

Rust made the same mistake and now a couple of times I've seen bugs like 
these being reported. Never seen them in Java or .Net though. I wonder 
why...