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copied!<p>One way might be to use the Bifunctor instance:</p> <pre><code>scala> val t = (Option(1), Option("str")) t: (Option[Int], Option[java.lang.String]) = (Some(1),Some(str)) scala> import scalaz._, Scalaz._, Tags._ import scalaz._ import Scalaz._ import Tags._ scala> t.bimap(First, First) res0: (scalaz.package.@@[Option[Int],scalaz.Tags.First], scalaz.package.@@[Option[java.lang.String],scalaz.Tags.First]) = (Some(1),Some(str)) </code></pre> <p>A more idiomatic way (ok, a more generic way: would work for any tuple, tripple, etc.) would probably be using <a href="https://github.com/milessabin/shapeless" rel="nofollow noreferrer">shapeless</a> to turn your tuple into an <code>HList</code>, and then apply a natural transformation <code>Option[A] ~> Option[A] @@ First</code>. Here's a sketchy implementation of this:</p> <pre><code>scala> import scalaz._, Scalaz._, Tags._ import scalaz._ import Scalaz._ import Tags._ scala> import shapeless._, Tuples._, Nat._ import shapeless._ import Tuples._ import Nat._ scala> val t = (Option(1), Option("str")) t: (Option[Int], Option[String]) = (Some(1),Some(str)) scala> object optionToFirstoption extends (Option ~> FirstOption) { | def apply[A](fa: Option[A]): Option[A] @@ First = First(fa) | } defined module optionToFirstoption scala> t.hlisted.map(optionToFirstoption).tupled res1: (Option[Int] with scalaz.Tagged[scalaz.Tags.First], Option[String] with scalaz.Tagged[scalaz.Tags.First]) = (Some(1),Some(str)) </code></pre>

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