blob: 8c5dd043f9e48564d112af49f342dc01670f59b9 [file] [log] [blame]
// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
import 'dart:async';
/// A wrapper that forwards calls to a [Future].
class DelegatingFuture<T> implements Future<T> {
/// The wrapped [Future].
final Future<T> _future;
/// Creates a wrapper which throws if [future]'s value isn't an instance of
/// `T`.
/// This soundly converts a [Future] to a `Future<T>`, regardless of its
/// original generic type, by asserting that its value is an instance of `T`
/// whenever it's provided. If it's not, the future throws a [CastError].
@Deprecated('Use future.then((v) => v as T) instead.')
static Future<T> typed<T>(Future future) =>
future is Future<T> ? future : future.then((v) => v as T);
Stream<T> asStream() => _future.asStream();
Future<T> catchError(Function onError, {bool Function(Object error) test}) =>
_future.catchError(onError, test: test);
Future<S> then<S>(FutureOr<S> Function(T) onValue, {Function onError}) =>
_future.then(onValue, onError: onError);
Future<T> whenComplete(FutureOr action) => _future.whenComplete(action);
Future<T> timeout(Duration timeLimit, {FutureOr<T> Function() onTimeout}) =>
_future.timeout(timeLimit, onTimeout: onTimeout);