Tracking issue for str_checked_slicing

[nagisa]

slice::get_unchecked now takes ranges, whereas str takes explicit usize. str does not provide an explicit method to slice unsafely with ranges either.

[alexcrichton]

Should be a relatively easy API to add! I believe this just needs to mirror slices and can likely use the same trait for abstractions.

i'd like to do it

[Mark-Simulacrum]

Nominating for libs team discussion -- I think it's reasonable to stabilize this. It's been implemented for about two cycles (PR merged March 31st), I believe. The API surface is fairly small -- extending slice get{,_unchecked} methods to strs. It's possible we should deprecate the slice_unchecked{,_mut} methods as we stabilize this extension -- I believe they are obsoleted by this addition.

[alexcrichton]

@rfcbot fcp merge

Sounds good to me to stabilize!