feat: either chain-rec functor

soraLib · Jul 20, 2022 · 992160f · 992160f
1 parent 1c6aeb2
commit 992160f
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Showing 2 changed files with 8 additions and 4 deletions.
diff --git a/src/Either.ts b/src/Either.ts
@@ -313,9 +313,13 @@ export const Monad: Monad2<EitherKind> = {
   chain: _chain
 }
 
+/**
+ * ChainRec Functor
+ */
 export const ChainRec: ChainRec2<EitherKind> = {
   URI: EitherKind,
   map: _map,
   ap: _ap,
-  chain: _chain
+  chain: _chain,
+  chainRec: _chainRec
 }
diff --git a/src/Functors/ChainRec.ts b/src/Functors/ChainRec.ts
@@ -13,15 +13,15 @@ import { Chain, Chain1, Chain2 } from './Chain'
 import { Either } from '../Either'
 
 export interface ChainRec<F> extends Chain<F> {
-  readonly chainRec: <A, B>(fa: HKT<F, A>, f: (a: A) => Either<HKT<F, A>, HKT<F, B>>) => HKT<F, B>
+  readonly chainRec: <A, B>(fa: A, f: (a: A) => Either<HKT<F, A>, HKT<F, B>>) => HKT<F, B>
 }
 
 export interface ChainRec1<F extends URIS> extends Chain1<F> {
-  readonly chainRec: <A, B>(fa: KindOf<F, [A]>, f: (a: A) => Either<KindOf<F, [A]>, KindOf<F, [B]>>) => KindOf<F, [B]>
+  readonly chainRec: <A, B>(fa: A, f: (a: A) => Either<KindOf<F, [A]>, KindOf<F, [B]>>) => KindOf<F, [B]>
 }
 
 export interface ChainRec2<F extends URIS> extends Chain2<F> {
-  readonly chainRec: <E, A, B>(fa: KindOf<F, [E, A]>, f: (a: A) => KindOf<F, [E, Either<A, B>]>) => KindOf<F, [E, B]>
+  readonly chainRec: <E, A, B>(fa: A, f: (a: A) => KindOf<F, [E, Either<A, B>]>) => KindOf<F, [E, B]>
 }
 
 /**