feat(toPromise): now exists as a permanent method on Observable

src/Observable.ts

@@ -327,4 +327,29 @@ export class Observable<T> implements Subscribable<T> {
 
     return pipeFromArray(operations)(this);
   }
+
+  /* tslint:disable:max-line-length */
+  toPromise<T>(this: Observable<T>): Promise<T>;
+  toPromise<T>(this: Observable<T>, PromiseCtor: typeof Promise): Promise<T>;
+  toPromise<T>(this: Observable<T>, PromiseCtor: PromiseConstructorLike): Promise<T>;
+  /* tslint:enable:max-line-length */
+
+  toPromise(PromiseCtor?: PromiseConstructorLike) {
+    if (!PromiseCtor) {
+      if (root.Rx && root.Rx.config && root.Rx.config.Promise) {
+        PromiseCtor = root.Rx.config.Promise;
+      } else if (root.Promise) {
+        PromiseCtor = root.Promise;
+      }
+    }
+
+    if (!PromiseCtor) {
+      throw new Error('no Promise impl found');
+    }
+
+    return new PromiseCtor((resolve, reject) => {
+      let value: any;
+      this.subscribe((x: T) => value = x, (err: any) => reject(err), () => resolve(value));
+    }) as Promise<T>;
+  }
 }

src/add/operator/toPromise.ts

@@ -1,11 +1,2 @@
-
-import { Observable } from '../../Observable';
-import { toPromise } from '../../operator/toPromise';
-
-Observable.prototype.toPromise = toPromise;
-
-declare module '../../Observable' {
-  interface Observable<T> {
-    toPromise: typeof toPromise;
-  }
-}
+// HACK: does nothing, because `toPromise` now lives on the `Observable` itself.
+// leaving this module here to prevent breakage.

src/operator/toPromise.ts

@@ -1,5 +1,4 @@
 import { Observable } from '../Observable';
-import { toPromise as higherOrder } from '../operators/toPromise';
 
 /* tslint:disable:max-line-length */
 export function toPromise<T>(this: Observable<T>): Promise<T>;
@@ -57,5 +56,5 @@ export function toPromise<T>(this: Observable<T>, PromiseCtor: PromiseConstructo
  * @owner Observable
  */
 export function toPromise<T>(this: Observable<T>, PromiseCtor?: PromiseConstructorLike): Promise<T> {
-  return higherOrder(PromiseCtor)(this) as Promise<T>;
+  return this.toPromise();
 }

src/operators/toPromise.ts

@@ -1,5 +1,4 @@
 import { Observable } from '../Observable';
-import { root } from '../util/root';
 import { UnaryFunction } from '../interfaces';
 
 /* tslint:disable:max-line-length */
@@ -58,22 +57,5 @@ export function toPromise<T>(PromiseCtor: PromiseConstructorLike): UnaryFunction
  * @owner Observable
  */
 export function toPromise<T>(PromiseCtor?: PromiseConstructorLike): UnaryFunction<Observable<T>, Promise<T>> {
-  return (source: Observable<T>) => {
-    if (!PromiseCtor) {
-      if (root.Rx && root.Rx.config && root.Rx.config.Promise) {
-        PromiseCtor = root.Rx.config.Promise;
-      } else if (root.Promise) {
-        PromiseCtor = root.Promise;
-      }
-    }
-
-    if (!PromiseCtor) {
-      throw new Error('no Promise impl found');
-    }
-
-    return new PromiseCtor((resolve, reject) => {
-      let value: any;
-      source.subscribe((x: T) => value = x, (err: any) => reject(err), () => resolve(value));
-    }) as Promise<T>;
-  };
+  return (source: Observable<T>) => source.toPromise();
 }