feat: deferred

Author: kevinoneill

src/deferred.ts

@@ -0,0 +1,37 @@
+export class Deferred<T> implements PromiseLike<T> {
+  private promise: Promise<T>;
+
+  private resolver: (value?: T | PromiseLike<T>) => void = () => {
+    throw new Error("why wasn't i replaced");
+  };
+  private rejector: (reason?: any) => void = () => {
+    throw new Error("why wasn't i replaced");
+  };
+
+  constructor() {
+    this.promise = new Promise<T>((resolve, reject) => {
+      this.resolver = resolve;
+      this.rejector = reject;
+    });
+  }
+
+  get then() {
+    return this.promise.then.bind(this.promise);
+  }
+
+  get catch() {
+    return this.promise.catch.bind(this.promise);
+  }
+
+  get finally() {
+    return this.promise.finally.bind(this.promise);
+  }
+
+  resolve(value: T) {
+    this.resolver(value);
+  }
+
+  reject(reason: any) {
+    this.rejector(reason);
+  }
+}

src/index.ts

@@ -2,4 +2,5 @@ export * from "./types";
 export * from "./semaphore";
 export * from "./mutex";
 export * from "./latch";
+export * from "./deferred";
 export { TimeoutError, isTimeout } from "./utilities/timeout";