Добавлены методы chainError и chainErrorTo

eff/index.ts

@@ -37,15 +37,17 @@ declare module 'rxjs/internal/Observable' {
 
     performSuccess<R,A>(this: Eff<never, R>, onSuccess: (x: R) => A): Cmd<A>;
 
-    onError<L,R,L2,R2>(this: Eff<L, R>, onFailure: (x: L) => Eff<L2, R2>): Eff<L2, R2|R>;
-
     chain<L,R,R2>(this: Eff<L, R>, f: (x: R) => Eff<L, R2>): Eff<L, R2>;
     chain<L,R,L2,R2>(this: Eff<L, R>, f: (x: R) => Eff<L2, R2>): Eff<L|L2, R2>;
 
     chainTo<L,R,R2>(this: Eff<L, R>, effect: Eff<L, R2>): Eff<L, R2>;
     chainTo<L,R,L2,R2>(this: Eff<L, R>, effect: Eff<L2, R2>): Eff<L|L2, R2>;
 
+    chainError<L,R,L2,R2>(this: Eff<L, R>, onFailure: (x: L) => Eff<L2, R2>): Eff<L2, R2|R>;
+    chainErrorTo<L,R,L2,R2>(this: Eff<L, R>, onFailure: Eff<L2, R2>): Eff<L2, R2|R>;
+
     // DEPRECATED
+    onError<L,R,L2,R2>(this: Eff<L, R>, onFailure: (x: L) => Eff<L2, R2>): Eff<L2, R2|R>;
     chainEff<L,R,R2>(this: Eff<L, R>, f: (x: R) => Eff<L, R2>): Eff<L, R2>;
     chainEff<L,R,L2,R2>(this: Eff<L, R>, f: (x: R) => Eff<L2, R2>): Eff<L|L2, R2>;
     mapEff<L,R,R2>(this: Eff<L, R>, f: (x: R) => R2): Eff<L, R2>;
@@ -73,6 +75,14 @@ declare module 'rxjs/internal/Observable' {
   return this.pipe(map((ethr: Either<any, any>) => ethr.tag === 'Left' ? onFailure(ethr.value) : Rx.of(ethr)), combineAll(x => x));
 };
 
+(Observable as any).prototype.chainError = function<L,R,L2,R2>(this: Eff<L, R>, onFailure: (x: L) => Eff<L2, R2>): Eff<L2, R2|R> {
+  return this.pipe(map((ethr: Either<any, any>) => ethr.tag === 'Left' ? onFailure(ethr.value) : Rx.of(ethr)), combineAll(x => x));
+};
+
+(Observable as any).prototype.chainErrorTo = function<L,R,L2,R2>(this: Eff<L, R>, onFailure: Eff<L2, R2>): Eff<L2, R2|R> {
+  return this.pipe(map((ethr: Either<any, any>) => ethr.tag === 'Left' ? onFailure : Rx.of(ethr)), combineAll(x => x));
+};
+
 (Observable as any).prototype.chain = function<L,R,R2>(this: Eff<L, R>, f: (x: R) => Eff<L, R2>): Eff<L, R2> {
   return this.pipe(map(ethr => ethr.tag === 'Right' ? f(ethr.value) : Rx.of(ethr)), combineAll(x => x as Either<any , any>));
 };