fix ChainRec definition

CHANGELOG.md

@@ -0,0 +1,23 @@
+# Changelog
+
+> **Tags:**
+> - [New Feature]
+> - [Bug Fix]
+> - [Breaking Change]
+> - [Documentation]
+> - [Internal]
+> - [Polish]
+> - [Experimental]
+
+**Note**: Gaps between patch versions are faulty/broken releases.
+**Note**: A feature tagged as Experimental is in a high state of flux, you're at risk of it changing without notice.
+
+# 0.0.2
+
+- **Bug Fix**
+  - fix `ChainRec` definition (@gcanti)
+
+# 0.0.1
+
+Initial release
+

package.json

@@ -1,6 +1,6 @@
 {
   "name": "fp-ts",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "description": "Functional programming in TypeScript",
   "files": [
     "lib",

src/ChainRec.ts

@@ -5,9 +5,11 @@ import { isLeft } from './Either'
 import { Function1 } from './function'
 
 export interface ChainRec<M> extends Chain<M> {
-  chainRec<A, B>(f: Function1<A, HKT<M, Either<A, B>>>, a: A): B;
+  /** forall a b. (a -> m (Either a b)) -> a -> m b */
+  chainRec<A, B>(f: Function1<A, HKT<M, Either<A, B>>>, a: A): HKT<M, B>;
 }
 
+/** forall a b. (a -> Either a b) -> a -> b */
 export function tailRec<A, B>(f: Function1<A, Either<A, B>>, a: A): B {
   let v = f(a)
   while (isLeft(v)) {