data
An implementation of Func that's specialized to Applicative.
Represents a function F[A] => B.
Const is a phantom type, it does not contain a value of its second type parameter B
Const can be seen as a type level version of Function.const[A, B]: A => B => A
F on the left and G on the right of Xor.
Func is a function A => F[B].
Func is a function A => F[B].
Represents a right-biased disjunction that is either an A, or a B, or both an A and a B.
Represents a right-biased disjunction that is either an A, or a B, or both an A and a B.
An instance of A Ior B is one of:
A Ior B is similar to A Xor B, except that it can represent the simultaneous presence of
an A and a B. It is right-biased like Xor, so methods such as map and flatMap operate on the
B value. Some methods, like flatMap, handle the presence of two Both values using a
Semigroup[A], while other methods, like toXor, ignore the A value in a Both.
A Ior B is isomorphic to (A Xor B) Xor (A, B), but provides methods biased toward B
values, regardless of whether the B values appear in a Right or a Both.
The isomorphic Xor form can be accessed via the unwrap method.
Represents a function A => F[B].
A data type which represents a single element (head) and some other structure (tail).
A data type which represents a single element (head) and some other structure (tail). As we have done in package.scala, this can be used to represent a List which is guaranteed to not be empty:
type NonEmptyList[A] = OneAnd[List, A]
OptionT[F[_], A] is a light wrapper on an F[Option[A]] with some
convenient methods for working with this nested structure.
OptionT[F[_], A] is a light wrapper on an F[Option[A]] with some
convenient methods for working with this nested structure.
It may also be said that OptionT is a monad transformer for Option.
For more information, see the documentation.
Prod is a product to two independent functor values.
Prod is a product to two independent functor values.
StateT[F, S, A] is similar to Kleisli[F, S, A] in that it takes an S
argument and produces an A value wrapped in F.
StateT[F, S, A] is similar to Kleisli[F, S, A] in that it takes an S
argument and produces an A value wrapped in F. However, it also produces
an S value representing the updated state (which is wrapped in the F
context along with the A value.
Represents a right-biased disjunction that is either an A or a B.
Represents a right-biased disjunction that is either an A or a B.
An instance of A Xor B is either a Left[A] or a Right[B].
A common use of Xor is to explicitly represent the possibility of failure in a result as opposed to
throwing an exception. By convention, Left is used for errors and Right is reserved for successes.
For example, a function that attempts to parse an integer from a string may have a return type of
NumberFormatException Xor Int. However, since there is no need to actually throw an exception, the type (A)
chosen for the "left" could be any type representing an error and has no need to actually extend Exception.
A Xor B is isomorphic to scala.Either[A, B], but Xor is right-biased, so methods such as map and
flatMap apply only in the context of the "right" case. This right bias makes Xor more convenient to use
than scala.Either in a monadic context. Methods such as swap, and leftMap provide functionality
that scala.Either exposes through left projections.
Transformer for Xor, allowing the effect of an arbitrary type constructor F to be combined with the
fail-fast effect of Xor.
Transformer for Xor, allowing the effect of an arbitrary type constructor F to be combined with the
fail-fast effect of Xor.
XorT[F, A, B] wraps a value of type F[A Xor B]. An F[C] can be lifted in to XorT[F, A, C] via XorT.right,
and lifted in to a XorT[F, C, B] via XorT.left.