Wrapping<T> needs many different impls to make it useable

[strega-nil]

• Rem
• Shl
• Shr
• *Assign

Plus impl Op<T> for Wrapping<T>

[strega-nil]

It really is just an oversight. Wrapping<T> is sadly overlooked :(

[Eh2406]

There is a FIXME related to this issue,
https://github.com/rust-lang/rust/blob/master/src/test/run-pass/num-wrapping.rs#L70
https://github.com/rust-lang/rust/blob/master/src/test/run-pass/num-wrapping.rs#L176
Now that the issue is closed can the FIXME be fix, or made more specific?