refactor

src/async/impl.ts

@@ -7,7 +7,7 @@ import { AsyncRandomOptions } from "../random/types.js";
 import { selectionSorter } from "../sorting.js";
 import { Sequence } from "../sync/types.js";
 import { MaybeAsyncConverter, MaybeAsyncPredicate, MaybeAsyncEquater, MaybeAsyncBiConverter, MaybeAsyncAccumulator, MaybeAsyncComparer, MaybeAsyncAction, MaybePromiseLike, MaybeAsyncGenerator, MaybeAsyncSequence } from "../types.js";
-import { strictEquals, identity, operatorCompare, asAsyncGenerator, defaultArrayComparer, combineAsyncComparers } from "../utils.js";
+import { strictEquals, identity, operatorCompare, defaultArrayComparer, combineAsyncComparers, asAsyncIterable } from "../utils.js";
 import { array, empty, wrap } from "./index.js";
 import { AsyncSequence, GroupedAsyncSequence, OrderedAsyncSequence } from "./types.js";
 
@@ -1467,7 +1467,7 @@ class SkipWhileAsyncSequence<T> extends BaseAsyncSequence<T> {
       break;
     }
 
-    yield* asAsyncGenerator(iterator);
+    yield* asAsyncIterable(iterator);
   }
 }
 
@@ -1504,7 +1504,7 @@ class SkipLastAsyncSequence<T> extends BaseAsyncSequence<T> {
 
     i = 0;
 
-    for await (const obj of asAsyncGenerator(iterator)) {
+    for await (const obj of asAsyncIterable(iterator)) {
       yield buffer[i];
       buffer[i] = obj;
       i = (i + 1) % this.#n;
@@ -1540,7 +1540,7 @@ class SkipAsyncSequence<T> extends BaseAsyncSequence<T> {
       i++;
     } while (i < this.#n);
 
-    yield* asAsyncGenerator(iterator);
+    yield* asAsyncIterable(iterator);
   }
 }
 
@@ -1705,23 +1705,17 @@ class PrependAsyncSequence<T> extends BaseAsyncSequence<T> {
   }
 }
 
-class PeekAsyncSequence<T> extends BaseAsyncSequence<T> {
-  readonly #sequence: AsyncSequence<T>;
+class PeekAsyncSequence<T> extends DelegatedAsyncSequence<T> {
   readonly #action: MaybeAsyncAction<T>;
 
   constructor(sequence: AsyncSequence<T>, action: MaybeAsyncAction<T>) {
-    super();
+    super(sequence);
 
-    this.#sequence = sequence;
     this.#action = action;
   }
 
-  override async nonEnumeratedCount() {
-    return await this.#sequence.nonEnumeratedCount();
-  }
-
   override async *iterator() {
-    for await (const obj of this.#sequence) {
+    for await (const obj of this.sequence) {
       await this.#action(obj);
       yield obj;
     }
@@ -1995,13 +1989,15 @@ class GroupByAsyncSequence<TElement, TKey, TResult> extends BaseAsyncSequence<Gr
 
     for await (const obj of this.#sequence) {
       const key = await this.#keySelector(obj);
-      let grouping = await groupings.get(key);
+      const value = await this.#elementSelector(obj);
 
-      if (!grouping) {
-        await groupings.set(key, grouping = []);
+      const grouping = await groupings.get(key);
+
+      if (grouping) {
+        grouping.push(value);
+      } else {
+        await groupings.set(key, [value]);
       }
-
-      grouping.push(await this.#elementSelector(obj));
     }
 
     for (const entry of groupings) {