Index: packages/async/lib/src/delegate/sink.dart |
diff --git a/packages/async/lib/src/delegate/sink.dart b/packages/async/lib/src/delegate/sink.dart |
index bb50da33972521ff47578bf255566f0262c683ee..7c68a0fbc65f070f7f21556b7b8cda017f54e5cd 100644 |
--- a/packages/async/lib/src/delegate/sink.dart |
+++ b/packages/async/lib/src/delegate/sink.dart |
@@ -2,8 +2,6 @@ |
// 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. |
-library async.delegate.sink; |
- |
/// Simple delegating wrapper around a [Sink]. |
/// |
/// Subclasses can override individual methods, or use this to expose only the |
@@ -12,8 +10,18 @@ class DelegatingSink<T> implements Sink<T> { |
final Sink _sink; |
/// Create a delegating sink forwarding calls to [sink]. |
- DelegatingSink(Sink sink) |
- : _sink = sink; |
+ DelegatingSink(Sink<T> sink) : _sink = sink; |
+ |
+ DelegatingSink._(this._sink); |
+ |
+ /// Creates a wrapper that coerces the type of [sink]. |
+ /// |
+ /// Unlike [new DelegatingSink], this only requires its argument to be an |
+ /// instance of `Sink`, not `Sink<T>`. This means that calls to [add] may |
+ /// throw a [CastError] if the argument type doesn't match the reified type of |
+ /// [sink]. |
+ static Sink<T> typed<T>(Sink sink) => |
+ sink is Sink<T> ? sink : new DelegatingSink._(sink); |
void add(T data) { |
_sink.add(data); |