Interface MonadFail<M>

A monad with failure computation having an error message. An instance m of MonadFail must satisfy the following laws:

Annihilation: For all e and f; m.flatMap(f)(m.fail(e)) equals to m.fail(e).

interface MonadFail<M> {
    apply: <T, U>(
        fn: Instance<Apply1<M, (t: T) => U>>,
    ) => (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>;
    fail: <T>(message: string) => Get1<M, T>;
    flatMap: <T1, U1>(
        a: (t: T1) => Instance<Apply1<M, U1>>,
    ) => (t: Instance<Apply1<M, T1>>) => Instance<Apply1<M, U1>>;
    map: <T, U>(
        fn: (t: T) => U,
    ) => (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>;
    pure: <T>(t: T) => Instance<Apply1<M, T>>;
}

Type Parameters

M

Hierarchy (View Summary)

TypeClass.Monad.Monad<M>
- MonadFail

Index

Properties

apply fail flatMap map pure

Properties

`Readonly`apply

apply: <T, U>(
fn: Instance<Apply1<M, (t: T) => U>>,
) => (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>

Applies the function to the value over S.

Type Declaration

- <T, U>(
  fn: Instance<Apply1<M, (t: T) => U>>,
  ): (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>
- Type Parameters
  - T
  - U
  Parameters
  - fn: Instance<Apply1<M, (t: T) => U>>
    The wrapped function.
  Returns (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>
  The value got by evaluating fn.

`Readonly`fail

fail: <T>(message: string) => Get1<M, T>

`Readonly`flatMap

flatMap: <T1, U1>(
a: (t: T1) => Instance<Apply1<M, U1>>,
) => (t: Instance<Apply1<M, T1>>) => Instance<Apply1<M, U1>>

`Readonly`map

map: <T, U>(
fn: (t: T) => U,
) => (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>

Maps the function fn onto F structure.

Type Declaration

- <T, U>(fn: (t: T) => U): (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>
- Type Parameters
  - T
  - U
  Parameters
  - fn: (t: T) => U
    The function to be mapped.
  Returns (t: Instance<Apply1<M, T>>) => Instance<Apply1<M, U>>
  The mapped function.

`Readonly`pure

pure: <T>(t: T) => Instance<Apply1<M, T>>