The Chain
type class extends the Apply
type class with a chain
operation which composes computations in
sequence, using the return value of one computation to determine the next computation.
Instances must satisfy the following law in addition to the Apply
laws:
F.chain(F.chain(fa, afb), bfc) <-> F.chain(fa, a => F.chain(afb(a), bfc))
Note. Apply
's ap
can be derived: (fab, fa) => F.chain(fab, f => F.map(fa, f))
Added in v2.0.0
Signature
export interface Chain<F> extends Apply<F> {
readonly chain: <A, B>(fa: HKT<F, A>, f: (a: A) => HKT<F, B>) => HKT<F, B>
}
Added in v2.0.0
Signature
export interface Chain1<F extends URIS> extends Apply1<F> {
readonly chain: <A, B>(fa: Kind<F, A>, f: (a: A) => Kind<F, B>) => Kind<F, B>
}
Added in v2.0.0
Signature
export interface Chain2<F extends URIS2> extends Apply2<F> {
readonly chain: <E, A, B>(fa: Kind2<F, E, A>, f: (a: A) => Kind2<F, E, B>) => Kind2<F, E, B>
}
Added in v2.0.0
Signature
export interface Chain2C<F extends URIS2, E> extends Apply2C<F, E> {
readonly chain: <A, B>(fa: Kind2<F, E, A>, f: (a: A) => Kind2<F, E, B>) => Kind2<F, E, B>
}
Added in v2.0.0
Signature
export interface Chain3<F extends URIS3> extends Apply3<F> {
readonly chain: <R, E, A, B>(fa: Kind3<F, R, E, A>, f: (a: A) => Kind3<F, R, E, B>) => Kind3<F, R, E, B>
}
Added in v2.0.0
Signature
export interface Chain3C<F extends URIS3, E> extends Apply3C<F, E> {
readonly chain: <R, A, B>(fa: Kind3<F, R, E, A>, f: (a: A) => Kind3<F, R, E, B>) => Kind3<F, R, E, B>
}
Added in v2.2.0
Signature
export interface Chain4<F extends URIS4> extends Apply4<F> {
readonly chain: <S, R, E, A, B>(fa: Kind4<F, S, R, E, A>, f: (a: A) => Kind4<F, S, R, E, B>) => Kind4<F, S, R, E, B>
}
Added in v2.0.0