Deprecate Show

[nomisRev]

This PR deprecates Show since Kotlin, and Kotlin's Std doesn't take Show into account nor does Kotlin have the power to automatically derive or inject Show anywhere. This makes Show very cumbersome to work with, see Tuple10Show.kt.

The use-cases of Show seemed very limited and niche to us, so we've decided to exclude it from Arrow in 1.0.0. The common technique for this is to use data class, which automatically implements toString() and correctly implementing toString().

[franciscodr]

I was wondering why we need the toString method in the sealed class

[nomisRev]

I guess it's not needed if it's defined for all the cases.

[franciscodr]

I think we need to remove the instance of Show for Validated and its implementation:

• This line
• And this line

[franciscodr]

Thanks, @nomisRev!

[i-walker]

Thanks @nomisRev Looks great