Added promise progress

src/promise-progress.ts

@@ -0,0 +1,26 @@
+export type ProgressCallback = (progress: number) => any;
+
+export class PromiseProgress<T> extends Promise<T> {
+	private listeners: ProgressCallback[] = [];
+
+	private _progress = 0;
+	get progress() { return this._progress; }
+	set progress(p: number) {
+		if(p == this._progress) return;
+		this._progress = p;
+		this.listeners.forEach(l => l(p));
+	}
+
+	constructor(executor: (resolve: (value: T) => any, reject: (reason: any) => void, progress: (progress: number) => any) => void) {
+		super((resolve, reject) => executor(
+			(value: T) => resolve(value),
+			(reason: any) => reject(reason),
+			(progress: number) => this.progress = progress
+		));
+	}
+
+	onProgress(callback: ProgressCallback) {
+		this.listeners.push(callback);
+		return this;
+	}
+}