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    <p>You can use the fact that Scalaz 7 provides a <code>Bitraverse</code> instance for tuples and then sequence as usual (but with <code>bisequence</code> instead of <code>sequence</code>):</p> <pre><code>scala&gt; import scalaz._, std.option._, std.tuple._, syntax.bitraverse._ import scalaz._ import std.option._ import std.tuple._ import syntax.bitraverse._ scala&gt; val p: (Option[Int], Option[String]) = (Some(1), Some("a")) p: (Option[Int], Option[String]) = (Some(1),Some(a)) scala&gt; p.bisequence[Option, Int, String] res0: Option[(Int, String)] = Some((1,a)) </code></pre> <p>Unfortunately Scalaz 7 currently needs the type annotation here.</p> <hr> <p>In a comment Yo Eight states that the type annotation will remain mandatory here. I'm not sure what his or her reasoning is, but it's in fact perfectly easy to write your own wrapper that will provide any appropriately typed tuple with a <code>bisequence</code> method and won't require a type annotation:</p> <pre><code>import scalaz._, std.option._, std.tuple._ class BisequenceWrapper[F[_, _]: Bitraverse, G[_]: Applicative, A, B]( v: F[G[A], G[B]] ) { def bisequence = implicitly[Bitraverse[F]].bisequence(v) } implicit def bisequenceWrap[F[_, _]: Bitraverse, G[_]: Applicative, A, B]( v: F[G[A], G[B]] ) = new BisequenceWrapper(v) </code></pre> <p>Now <code>(some(1), some("a")).bisequence</code> will compile just fine.</p> <p>I can't think of a good reason Scalaz wouldn't include something like this. Whether or not you want to add it in the meantime is a matter of taste, but there's definitely no theoretical obstacle to letting the compiler do the typing here.</p>
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    1. POConverting a tuple of options to an option of tuple with Scalaz or Shapeless
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    1. COUnfortunately, type annotations will remain mandatory in this situation
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    2. CO@YoEight: Why do you say that? See my edit for a working example.
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    3. CO@Travis Brown. You've just deferred the problem. Your wrapper holds the type information for you. The very same information you would annotate at call site. I did the same trick when I pushed MonadWriter to Scalaz.
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