GDC adds intrinsic support for core.checkedint

[tsbockman via Digitalmars-d]

On Thursday, 2 July 2015 at 11:26:24 UTC, Robert burner Schadek 
wrote:
> On Thursday, 2 July 2015 at 00:29:46 UTC, rsw0x wrote:
>> all bitwise ops except for shifting are fundamental math 
>> operators just like addition and subtraction if you view an 
>> integer as a bitstring(which is what it is...)
>
> I must have missed something in my math classes.
>
> "Like the natural numbers, Z is closed under the operations of 
> addition and multiplication" [1]
>
> build in Integer are not really closed, but close enough.
> No mentioning of shift operations though.
>
> [1] https://en.wikipedia.org/wiki/Integer

I don't see why the closed-ness of the integers under an 
operation should determine whether it makes the cut or not, but 
if that's the standard:

The built-in integer types are truly closed under the bitwise 
operators `~`, `&`, `|`, and `^`, with no overflow, underflow, or 
undefined combinations.

In contrast, unary `-` can overflow, while binary `+`, `-`, and 
`*` can all overflow or underflow.

`<<` and `>>` are not closed, but they are conceptually identical 
to `* 2^^` and `/ 2^^`, respectively. Their invalid input 
combinations can be handled the same way.