diff --git a/src/vs/base/common/winjs.base.d.ts b/src/vs/base/common/winjs.base.d.ts
index 7e3ae270d949d..5cbbf2394a913 100644
--- a/src/vs/base/common/winjs.base.d.ts
+++ b/src/vs/base/common/winjs.base.d.ts
@@ -47,7 +47,7 @@ export declare class Promise {
  * The value callback to complete a promise
  */
 export interface TValueCallback<T> {
-	(value: T): void;
+	(value: T | Thenable<T>): void;
 }
 
 
diff --git a/src/vs/monaco.d.ts b/src/vs/monaco.d.ts
index 8e0f447643850..17f13a3cfaad2 100644
--- a/src/vs/monaco.d.ts
+++ b/src/vs/monaco.d.ts
@@ -47,7 +47,7 @@ declare module monaco {
 	 * The value callback to complete a promise
 	 */
 	export interface TValueCallback<T> {
-		(value: T): void;
+		(value: T | Thenable<T>): void;
 	}