Pop Quiz what is wrong with this code?

[Avrina]

On Sunday, 21 June 2020 at 10:12:22 UTC, Patrick Schluter wrote:
> On Saturday, 20 June 2020 at 23:36:25 UTC, Avrina wrote:
>> On Saturday, 20 June 2020 at 18:15:27 UTC, Steven 
>> Schveighoffer wrote:
>>> On 6/20/20 12:00 PM, Danni Coy wrote:
>>>
>>>> I tried explicitly making x and y ints and I got a 
>>>> depreciation warning.
>>>
>>> foreach(ptrdiff_t y, ref row; offsetMap)
>>>
>>> is that what you wanted?
>>>
>>> ptrdiff_t is the signed version of size_t. The complaint is 
>>> not that you are converting from unsigned to signed, but that 
>>> you are converting from 64-bit to 32-bit.
>>>
>>> -Steve
>>
>> Why isn't that deprecated as well? implicitly converting from 
>> ulong to long is an error as much as ulong to uint.
>
> No. conversion of ulong to uint loses 32 times more data than 
> conversion to long does.

Lol, it's not linear friend.

You lose around 18446744069414584319 values from ulong to uint, 
you lose 9223372032559808512 from ulong to long. Which is about 2 
times less data. Which makes sense as it is basically 2^64 - 
2^63, so of course it would only be x2 -- not x32.