On Monday, 24 November 2014 at 19:06:35 UTC, Matthias Bentrup
wrote:
There is no right or wrong in Mathematics, only true and false.
The result of modular addition with overflow is not wrong, it is
just different than the result of integer addition.
I think we are talking past each other. In my view the term
"overflow" has nothing to do with mathematics, overflow is a
signal from the ALU that the computation is incorrect e.g. not in
accordance with the intended type.
Agreed, though I don't like the explosion of new operators. I'd
prefer the C# syntax like check(<expression>), wrap(expression),
saturate(expression).
Yep, that is another way to do it. What is preferable probably
varies from case to case.
And can fail spectacularly in others. The compiler always has to
prepare for the worst case, i.e. the largest integer size
possible, while in practice you may need that only for a few
extreme cases.
In some loops it probably can get tricky to get it right without
help from the programmer. I believe some languages allow you to
annotate loops with an upper boundary to help the semantic
analysis, but you could also add more frequent overflow checks on
request?
