Revert "RFC: Improve core types for (Async) Iterable/Iterator/Generator"

This reverts commit 7d5bb51.

Whoops. Definitely did not mean to commit this before PR.

Author: leebyron

lib/core.js

@@ -547,21 +547,19 @@ type IteratorResult<Yield,Return> =
   | { done: true, value?: Return }
   | { done: false, value: Yield };
 
-interface $Iterable<+Yield,+Return,-Next> {
+interface $Iterator<+Yield,+Return,-Next> {
     @@iterator(): $Iterator<Yield,Return,Next>;
-}
-type Iterable<+T> = $Iterable<T,void,void>;
-
-interface $Iterator<+Yield,+Return,-Next> implements $Iterable<Yield,Return,Next> {
-    @@iterator(): this;
     next(value?: Next): IteratorResult<Yield,Return>;
-    return?: <R>(value: R) => IteratorResult<Yield,R|Return>;
-    throw?: (error?: any) => IteratorResult<Yield,Return>;
 }
 type Iterator<+T> = $Iterator<T,void,void>;
 
-interface Generator<+Yield,+Return,-Next> implements $Iterator<Yield,Return,Next> {
-    @@iterator(): this;
+interface $Iterable<+Yield,+Return,-Next> {
+    @@iterator(): $Iterator<Yield,Return,Next>;
+}
+type Iterable<+T> = $Iterable<T,void,void>;
+
+interface Generator<+Yield,+Return,-Next> {
+    @@iterator(): $Iterator<Yield,Return,Next>;
     next(value?: Next): IteratorResult<Yield,Return>;
     return<R>(value: R): IteratorResult<Yield,R|Return>;
     throw(error?: any): IteratorResult<Yield,Return>;
@@ -571,27 +569,25 @@ declare function $iterate<T>(p: Iterable<T>): T;
 
 /* Async Iterable/Iterator/Generator */
 
-interface $AsyncIterable<+Yield,+Return,-Next> {
+interface $AsyncIterator<+Yield,+Return,-Next> {
     @@asyncIterator(): $AsyncIterator<Yield,Return,Next>;
-}
-type AsyncIterable<+T> = $AsyncIterable<T,void,void>;
-
-interface $AsyncIterator<+Yield,+Return,-Next> implements $AsyncIterable<Yield,Return,Next> {
-    @@asyncIterator(): this;
     next(value?: Next): Promise<IteratorResult<Yield,Return>>;
-    return?: <R>(value: R) => Promise<IteratorResult<Yield,R|Return>>;
-    throw? (error?: any) => Promise<IteratorResult<Yield,Return>>;
 }
 type AsyncIterator<+T> = $AsyncIterator<T,void,void>;
 
-interface AsyncGenerator<+Yield,+Return,-Next> implements $AsyncIterator {
-    @@asyncIterator(): this;
+interface $AsyncIterable<+Yield,+Return,-Next> {
+    @@asyncIterator(): $AsyncIterator<Yield,Return,Next>;
+}
+type AsyncIterable<+T> = $AsyncIterable<T,void,void>;
+
+interface AsyncGenerator<+Yield,+Return,-Next> {
+    @@asyncIterator(): $AsyncIterator<Yield,Return,Next>;
     next(value?: Next): Promise<IteratorResult<Yield,Return>>;
     return<R>(value: R): Promise<IteratorResult<Yield,R|Return>>;
     throw(error?: any): Promise<IteratorResult<Yield,Return>>;
 }
 
-declare function $asyncIterate<T>(p: AsyncIterable<T>): T;
+declare function $asyncIterator<T>(p: AsyncIterable<T>): T;
 
 /* Maps and Sets */