std.experimental.checkedint is ready for comments!

[Walter Bright via Digitalmars-d]

On 6/15/2016 9:40 AM, Andrei Alexandrescu wrote:
> Looking at the IntFlagPolicy, it offers three canned behavior: throws, asserts,
> and noex. Users cannot customize behavior and there is no information passed
> into the policy (e.g. the operands in case of overflow, or the numerator in case
> of division by zero). Passing the appropriate information would make it possible
> to implement various policies, e.g. the policy cannot say "I'm actually okay
> with this" or "here I'll implement a saturation policy".

Just a note to add to these excellent comments. One style of integer arithmetic 
is "saturation" arithmetic, whereby if it overflows, instead of an error it gets 
"stuck" at T.max. Same for underflow.

   https://en.wikipedia.org/wiki/Saturation_arithmetic

A good test for a policy API design is if saturation behavior could be done with 
a user-defined policy, instead of it being a pre-defined one.