change project structure to remove namespaces

src/collector/index.ts

@@ -0,0 +1,56 @@
+import { Converter } from "../types.js";
+import { SimpleCollector, ToArrayCollector, ToObjectCollector, ToMapCollector, ToSetCollector, JoinCollector, SumCollector, BigIntSumCollector, AverageCollector, BigIntAverageCollector } from "./impl.js";
+import { Collector } from "./types.js";
+
+export function create<TElement, TAccumulator, TResult>(initialize: () => TAccumulator, accumulate: (accumulator: TAccumulator, element: TElement) => void,
+  finalize: (accumulator: TAccumulator) => TResult): Collector<TElement, TAccumulator, TResult> {
+  return new SimpleCollector(initialize, accumulate, finalize);
+}
+
+const toArrayCollector = new ToArrayCollector<any>();
+
+export function toArray<TElement>(): Collector<TElement, any, TElement[]> {
+  return toArrayCollector;
+}
+
+export function toObject<TElement, TKey extends PropertyKey, TValue>(keySelector: Converter<TElement, TKey>, valueSelector: Converter<TElement, TValue>): Collector<TElement, any, Record<TKey, TValue>> {
+  return new ToObjectCollector<TElement, TKey, TValue>(keySelector, valueSelector);
+}
+
+export function toMap<TElement, TKey, TValue>(keySelector: Converter<TElement, TKey>, valueSelector: Converter<TElement, TValue>): Collector<TElement, any, Map<TKey, TValue>> {
+  return new ToMapCollector<TElement, TKey, TValue>(keySelector, valueSelector);
+}
+
+const toSetCollector = new ToSetCollector<any>();
+
+export function toSet<TElement>(): Collector<TElement, any, Set<TElement>> {
+  return toSetCollector;
+}
+
+export function join(delimiter?: string, prefix?: string, suffix?: string): Collector<any, any, string> {
+  return new JoinCollector(delimiter, prefix, suffix);
+}
+
+const sumCollector = new SumCollector();
+
+export function sum(): Collector<number, any, number> {
+  return sumCollector;
+}
+
+const bigintSumCollector = new BigIntSumCollector();
+
+export function bigintSum(): Collector<bigint, any, bigint> {
+  return bigintSumCollector;
+}
+
+const averageCollector = new AverageCollector();
+
+export function average(): Collector<number, any, number> {
+  return averageCollector;
+}
+
+const bigintAverageCollector = new BigIntAverageCollector();
+
+export function bigintAverage(): Collector<bigint, any, bigint> {
+  return bigintAverageCollector;
+}