rename Sequence sequenceX, traverseX and deprecate Sequence.some

[i-walker]

Rename to either sequence or traverse:

• sequenceEither
• sequenceValidated
• sequenceOption
• traverseEither
• traverseOption
• traverseValidated

Deprecate:

• some

[raulraja]

What is the replacement that a user would perform in this case? The current message is a bit cryptic. If we know the expression that would replace sequenceeEither then we can add it to a ReplaceWith.

[i-walker]

here a user could opt to use toList().sequenceEither() instead, if that sounds good to all, I can add it?

[nomisRev]

There are several options here:

• Deprecate and change the signature to Sequence<Either<E, A>>.sequenceEither(): Either<E, List<A>>, which doesn't lie about the fact that it's terminal. This would be more optimized than toList().sequenceEither().

• Deprecate and ReplaceWith toList().sequenceEither().

Now that I think about it, the latter might be problematic since that cannot short-circuit an infinite Sequence on Either.Left but deprecating towards a List in the return type is going to be very difficult without breaking the Kotlin API (the binary can be kept in tact by using HIDDEN).

[raulraja]

It looks excellent @i-walker, thanks. Since we are renaming sequenceX to sequence, is there a better name for this operation?. I feel in Kotlin this operation may be confusing by name, and you'd think you'd get a Sequence back instead of traversing over identity.

[i-walker]

Since sequence == traverse(::identity) we could introduce f to have a default value ::identity for 2.0. Then we could drop sequence since the Traverse type class doesn't exist anymore
wdyt @raulraja ?