Transforms an Option
into an OptionT
, lifted into the specified Applicative
.
Transforms an Option
into an OptionT
, lifted into the specified Applicative
.
scala> import cats.implicits._ scala> val o: Option[Int] = Some(2) scala> OptionT.fromOption[List](o) res0: OptionT[List, Int] = OptionT(List(Some(2)))
Lifts the F[A]
Functor into an OptionT[F, A]
.
Same as liftF, but expressed as a FunctionK for use with mapK
Same as liftF, but expressed as a FunctionK for use with mapK
scala> import cats._, data._, implicits._ scala> val a: EitherT[Eval, String, Int] = 1.pure[EitherT[Eval, String, ?]] scala> val b: EitherT[OptionT[Eval, ?], String, Int] = a.mapK(OptionT.liftK) scala> b.value.value.value res0: Option[Either[String,Int]] = Some(Right(1))
Creates a OptionT[A]
from an A
Creates a OptionT[A]
from an A
scala> import cats.implicits._ scala> OptionT.pure[List](2) res0: OptionT[List, Int] = OptionT(List(Some(2)))
An alias for pure
An alias for pure
scala> import cats.implicits._ scala> OptionT.some[List](2) res0: OptionT[List, Int] = OptionT(List(Some(2)))