diff --git a/core-lib/es6/src/main/java/def/js/Promise.java b/core-lib/es6/src/main/java/def/js/Promise.java
index bd4e16bf..8b464c0b 100644
--- a/core-lib/es6/src/main/java/def/js/Promise.java
+++ b/core-lib/es6/src/main/java/def/js/Promise.java
@@ -1,181 +1,283 @@
 package def.js;
 
 import java.util.function.BiConsumer;
+import java.util.function.Consumer;
+import java.util.function.Function;
+
+import jsweet.util.Lang;
 
 /**
- * Represents the completion of an asynchronous operation
+ * Represents the completion of an asynchronous operation. <br />
+ * <b>Warning:</b> in JSweet, this definition is slightly modifed because of
+ * Java type erasure & modified keywords. For instance <code>catch</code> is
+ * Catch, <code>then</code> with chained Promise is thenAsync. <br />
+ * <br />
+ * <b>Note:</b> this class could be used along with {@link Lang#async} / {@link Lang#await}. This is sweet!
+ * <br /><br />
+ * <b>Example:</b><br/>
+ * <code>
+ *  getAnswer(5000) <br/>
+	&nbsp;&nbsp;.then(result -> { <br/>
+	&nbsp;&nbsp;&nbsp;&nbsp;console.log("you have waited long enough to know that the answer is: " + result); <br/>
+	&nbsp;&nbsp;}); <br/>
+<br/><br/>
+	private Promise<Integer> getAnswer(int millis) { <br/>
+	&nbsp;&nbsp;return new Promise<Integer>((Consumer<Integer> resolve, Consumer<Object> reject) -> { <br/>
+	&nbsp;&nbsp;&nbsp;&nbsp;setTimeout(function(__ -> { <br/>
+	&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;resolve.accept(42); <br/>
+	&nbsp;&nbsp;&nbsp;&nbsp;}), millis); <br/>
+	&nbsp;&nbsp;}); <br/>
+	} <br/>
+ * </code>
  */
 public class Promise<T> extends def.js.Object {
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledFunctionOnrejectedFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Function<java.lang.Object,TResult> onrejected);
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Consumer<java.lang.Object> onrejected);
-    /**
-     * Attaches a callback for only the rejection of the Promise.
-     * @param onrejected The callback to execute when the Promise is rejected.
-     * @returns A Promise for the completion of the callback.
-     */
-    @jsweet.lang.Name("catch")
-    native public Promise<T> catchOnrejectedFunction(java.util.function.Function<java.lang.Object,T> onrejected);
-    native public java.lang.String $get(Symbol toStringTag);
-    /** 
-      * A reference to the prototype. 
-      */
-    public static Promise<?> prototype;
-    
-    /**
-     * Creates a Promise that is resolved with an array of results when all of the provided Promises 
-     * resolve, or rejected when any Promise is rejected.
-     * @param values An array of Promises.
-     * @returns A new Promise.
-     */
-    native public static <T> Promise<T[]> all(IterableT<T> values);
-    /**
-     * Creates a Promise that is resolved or rejected when any of the provided Promises are resolved 
-     * or rejected.
-     * @param values An array of Promises.
-     * @returns A new Promise.
-     */
-    native public static <T> Promise<T> race(IterableT<T> values);
-    /**
-     * Creates a new rejected promise for the provided reason.
-     * @param reason The reason the promise was rejected.
-     * @returns A new rejected Promise.
-     */
-    native public static Promise<Void> reject(java.lang.Object reason);
-    /**
-      * Creates a new resolved promise for the provided value.
-      * @param value A promise.
-      * @returns A promise whose internal state matches the provided promise.
-      */
-    native public static <T> Promise<T> resolve(T value);
-    /**
-     * Creates a new resolved promise .
-     * @returns A resolved promise.
-     */
-    native public static Promise<Void> resolve();
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledFunction(java.util.function.Function<T,TResult> onfulfilled);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    native public <TResult> Promise<TResult> then();
-    /**
-     * Attaches a callback for only the rejection of the Promise.
-     * @param onrejected The callback to execute when the Promise is rejected.
-     * @returns A Promise for the completion of the callback.
-     */
-    @jsweet.lang.Name("catch")
-    native public Promise<T> Catch();
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledFunctionOnrejectedPromiseLikeFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Function<java.lang.Object,PromiseLike<TResult>> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledPromiseLikeFunctionOnrejectedPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Function<java.lang.Object,PromiseLike<TResult>> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledPromiseLikeFunctionOnrejectedFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Function<java.lang.Object,TResult> onrejected);
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Consumer<java.lang.Object> onrejected);
-    /**
-     * Attaches a callback for only the rejection of the Promise.
-     * @param onrejected The callback to execute when the Promise is rejected.
-     * @returns A Promise for the completion of the callback.
-     */
-    @jsweet.lang.Name("catch")
-    native public Promise<T> catchOnrejectedPromiseLikeFunction(java.util.function.Function<java.lang.Object,PromiseLike<T>> onrejected);
-    /**
-     * Creates a new Promise.
-     * @param executor A callback used to initialize the promise. This callback is passed two arguments: 
-     * a resolve callback used resolve the promise with a value or the result of another promise, 
-     * and a reject callback used to reject the promise with a provided reason or error.
-     */
-    public Promise(ExecutorPromiseLikeBiConsumer<java.util.function.Consumer<PromiseLike<T>>,java.util.function.Consumer<java.lang.Object>> executor){}
-    
-    /**
-     * Creates a new Promise.
-     * @param executor A callback used to initialize the promise. This callback is passed two arguments: 
-     * a resolve callback used resolve the promise with a value or the result of another promise, 
-     * and a reject callback used to reject the promise with a provided reason or error.
-     */
-    public Promise(BiConsumer<java.util.function.Consumer<T>,java.util.function.Consumer<java.lang.Object>> executor){}
-    
-    /**
-     * Creates a Promise that is resolved with an array of results when all of the provided Promises 
-     * resolve, or rejected when any Promise is rejected.
-     * @param values An array of Promises.
-     * @returns A new Promise.
-     */
-    native public static <T> Promise<T[]> all(IterablePromiseLikeT<T> values);
-    /**
-     * Creates a Promise that is resolved or rejected when any of the provided Promises are resolved 
-     * or rejected.
-     * @param values An array of Promises.
-     * @returns A new Promise.
-     */
-    native public static <T> Promise<T> race(IterablePromiseLikeT<T> values);
-    /**
-      * Creates a new resolved promise for the provided value.
-      * @param value A promise.
-      * @returns A promise whose internal state matches the provided promise.
-      */
-    native public static <T> Promise<T> resolve(PromiseLike<T> value);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> Promise<TResult> thenOnfulfilledPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled);
-    protected Promise(){}
-    /** This functional interface should be used for disambiguating lambdas in function parameters (by casting to this interface).<p>It was automatically generated for functions (taking lambdas) that lead to the same erased signature. */
-    @java.lang.FunctionalInterface()
-    @jsweet.lang.Erased
-    public interface ExecutorPromiseLikeBiConsumer<T1,T2> {
-        public void $apply(T1 p1, T2 p2);
-    }
-    
-    /** This class was automatically generated for disambiguating erased method signatures. */
-    @jsweet.lang.Erased
-    public static class IterableT<T> extends def.js.Object {
-        public IterableT(Iterable<T> values){}
-    }
-    /** This class was automatically generated for disambiguating erased method signatures. */
-    @jsweet.lang.Erased
-    public static class IterablePromiseLikeT<T> extends def.js.Object {
-        public IterablePromiseLikeT(Iterable<PromiseLike<T>> values){}
-    }
-}
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> then(Function<T, TResult> onfulfilled,
+			Function<java.lang.Object, TResult> onrejected);
 
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> then(Function<T, TResult> onfulfilled,
+			java.util.function.Consumer<java.lang.Object> onrejected);
+
+	/**
+	 * Attaches a callback for only the rejection of the Promise.
+	 * 
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of the callback.
+	 */
+	@jsweet.lang.Name("catch")
+	native public Promise<T> Catch(Function<java.lang.Object, T> onrejected);
+
+	@jsweet.lang.Name("catch")
+	native public Promise<T> Catch(Consumer<java.lang.Object> onrejected);
+
+	native public java.lang.String $get(Symbol toStringTag);
+
+	/**
+	 * A reference to the prototype.
+	 */
+	public static Promise<?> prototype;
+
+	/**
+	 * Creates a Promise that is resolved with an array of results when all of the
+	 * provided Promises resolve, or rejected when any Promise is rejected.
+	 * 
+	 * @param values
+	 *            An array of Promises.
+	 * @returns A new Promise.
+	 */
+	native public static <T> Promise<T[]> all(IterableT<T> values);
+
+	/**
+	 * Creates a Promise that is resolved or rejected when any of the provided
+	 * Promises are resolved or rejected.
+	 * 
+	 * @param values
+	 *            An array of Promises.
+	 * @returns A new Promise.
+	 */
+	native public static <T> Promise<T> race(IterableT<T> values);
+
+	/**
+	 * Creates a new rejected promise for the provided reason.
+	 * 
+	 * @param reason
+	 *            The reason the promise was rejected.
+	 * @returns A new rejected Promise.
+	 */
+	native public static Promise<Void> reject(java.lang.Object reason);
+
+	/**
+	 * Creates a new resolved promise for the provided value.
+	 * 
+	 * @param value
+	 *            A promise.
+	 * @returns A promise whose internal state matches the provided promise.
+	 */
+	native public static <T> Promise<T> resolve(T value);
+
+	/**
+	 * Creates a new resolved promise .
+	 * 
+	 * @returns A resolved promise.
+	 */
+	native public static Promise<Void> resolve();
+
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	native public <TResult> Promise<TResult> then(Function<T, TResult> onfulfilled);
+
+	native public Promise<Void> then(Consumer<T> onfulfilled);
+
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> thenAsyncOnError(Function<T, TResult> onfulfilled,
+			Function<java.lang.Object, PromiseLike<TResult>> onrejected);
+
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> thenAsyncWithOnError(Function<T, PromiseLike<TResult>> onfulfilled,
+			Function<java.lang.Object, PromiseLike<TResult>> onrejected);
+
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> thenAsync(Function<T, PromiseLike<TResult>> onfulfilled,
+			Function<java.lang.Object, TResult> onrejected);
+
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> thenAsync(Function<T, PromiseLike<TResult>> onfulfilled,
+			java.util.function.Consumer<java.lang.Object> onrejected);
+
+	/**
+	 * Attaches a callback for only the rejection of the Promise.
+	 * 
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of the callback.
+	 */
+	@jsweet.lang.Name("catch")
+	native public Promise<T> catchAsync(Function<java.lang.Object, PromiseLike<T>> onrejected);
+
+	/**
+	 * Creates a new Promise.
+	 * 
+	 * @param executor
+	 *            A callback used to initialize the promise. This callback is passed
+	 *            two arguments: a resolve callback used resolve the promise with a
+	 *            value or the result of another promise, and a reject callback used
+	 *            to reject the promise with a provided reason or error.
+	 */
+	public Promise(
+			ExecutorPromiseLikeBiConsumer<java.util.function.Consumer<PromiseLike<T>>, java.util.function.Consumer<java.lang.Object>> executor) {
+	}
+
+	/**
+	 * Creates a new Promise.
+	 * 
+	 * @param executor
+	 *            A callback used to initialize the promise. This callback is passed
+	 *            two arguments: a resolve callback used resolve the promise with a
+	 *            value or the result of another promise, and a reject callback used
+	 *            to reject the promise with a provided reason or error.
+	 */
+	public Promise(BiConsumer<java.util.function.Consumer<T>, java.util.function.Consumer<java.lang.Object>> executor) {
+	}
+
+	/**
+	 * Creates a Promise that is resolved with an array of results when all of the
+	 * provided Promises resolve, or rejected when any Promise is rejected.
+	 * 
+	 * @param values
+	 *            An array of Promises.
+	 * @returns A new Promise.
+	 */
+	native public static <T> Promise<T[]> all(IterablePromiseLikeT<T> values);
+
+	/**
+	 * Creates a Promise that is resolved or rejected when any of the provided
+	 * Promises are resolved or rejected.
+	 * 
+	 * @param values
+	 *            An array of Promises.
+	 * @returns A new Promise.
+	 */
+	native public static <T> Promise<T> race(IterablePromiseLikeT<T> values);
+
+	/**
+	 * Creates a new resolved promise for the provided value.
+	 * 
+	 * @param value
+	 *            A promise.
+	 * @returns A promise whose internal state matches the provided promise.
+	 */
+	native public static <T> Promise<T> resolve(PromiseLike<T> value);
+
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	@jsweet.lang.Name("then")
+	native public <TResult> Promise<TResult> thenAsync(Function<T, PromiseLike<TResult>> onfulfilled);
+
+	protected Promise() {
+	}
+
+	/**
+	 * This functional interface should be used for disambiguating lambdas in
+	 * function parameters (by casting to this interface).
+	 * <p>
+	 * It was automatically generated for functions (taking lambdas) that lead to
+	 * the same erased signature.
+	 */
+	@java.lang.FunctionalInterface()
+	@jsweet.lang.Erased
+	public interface ExecutorPromiseLikeBiConsumer<T1, T2> {
+		public void $apply(T1 p1, T2 p2);
+	}
+
+	/**
+	 * This class was automatically generated for disambiguating erased method
+	 * signatures.
+	 */
+	@jsweet.lang.Erased
+	public static class IterableT<T> extends def.js.Object {
+		public IterableT(Iterable<T> values) {
+		}
+	}
+
+	/**
+	 * This class was automatically generated for disambiguating erased method
+	 * signatures.
+	 */
+	@jsweet.lang.Erased
+	public static class IterablePromiseLikeT<T> extends def.js.Object {
+		public IterablePromiseLikeT(Iterable<PromiseLike<T>> values) {
+		}
+	}
+}
diff --git a/core-lib/es6/src/main/java/def/js/PromiseLike.java b/core-lib/es6/src/main/java/def/js/PromiseLike.java
index 04cee2d2..75f8276f 100644
--- a/core-lib/es6/src/main/java/def/js/PromiseLike.java
+++ b/core-lib/es6/src/main/java/def/js/PromiseLike.java
@@ -1,64 +1,17 @@
 package def.js;
+
+import java.util.function.Function;
+
 @jsweet.lang.Interface
 public abstract class PromiseLike<T> extends def.js.Object {
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledFunctionOnrejectedFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Function<java.lang.Object,TResult> onrejected);
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Consumer<java.lang.Object> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledFunction(java.util.function.Function<T,TResult> onfulfilled);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    native public <TResult> PromiseLike<TResult> then();
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledPromiseLikeFunctionOnrejectedFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Function<java.lang.Object,TResult> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledFunctionOnrejectedPromiseLikeFunction(java.util.function.Function<T,TResult> onfulfilled, java.util.function.Function<java.lang.Object,PromiseLike<TResult>> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledPromiseLikeFunctionOnrejectedPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Function<java.lang.Object,PromiseLike<TResult>> onrejected);
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled, java.util.function.Consumer<java.lang.Object> onrejected);
-    /**
-    * Attaches callbacks for the resolution and/or rejection of the Promise.
-    * @param onfulfilled The callback to execute when the Promise is resolved.
-    * @param onrejected The callback to execute when the Promise is rejected.
-    * @returns A Promise for the completion of which ever callback is executed.
-    */
-    @jsweet.lang.Name("then")
-    native public <TResult> PromiseLike<TResult> thenOnfulfilledPromiseLikeFunction(java.util.function.Function<T,PromiseLike<TResult>> onfulfilled);
+	/**
+	 * Attaches callbacks for the resolution and/or rejection of the Promise.
+	 * 
+	 * @param onfulfilled
+	 *            The callback to execute when the Promise is resolved.
+	 * @param onrejected
+	 *            The callback to execute when the Promise is rejected.
+	 * @returns A Promise for the completion of which ever callback is executed.
+	 */
+	native public <TResult> PromiseLike<TResult> then(Function<T, ?> onfulfilled, def.js.Function onrejected);
 }
-