Brief Description of Changes

Set the SkipOptionalPointer property to true for all array schema types.

Effectively, this means an optional []int still has type []int, instead of the old *[]int.

Rationale

I don't find any functional difference in treating an []int and an *[]int. See:

• https://play.golang.com/p/cwtJGJlPsR0 ([]int version)
• https://play.golang.com/p/RrO-DpY7dqD (*[]int version)

They both:

• Can disambiguate between absent field (nil value) and empty array case (where both are non-nil).
• Cannot disambiguate between absent field and NULL value.

On the other hand, *[]T are much more clumsy to work with, due to the additional referencing/dereferencing
required.

Some libraries that rely on the polymorphic behaviour of len (on arrays and maps) cannot be used,
forcing the user to check for nil and dereferencing the *[]T as input.
ozzo-validaion's Length check is one of them.

Breaking Change

Yes, this is a breaking change (it functionally changes some test examples).

However, I believe this makes the user experience much better.