Add browser-compatible version.

lib/src/resource.dart

Index: lib/src/resource.dart
diff --git a/lib/src/resource.dart b/lib/src/resource.dart
index 924ec051b364e38c6fa90bd3867704bb2100f69f..24cbd513387ac29efcb98be574094514e73f1b6d 100644
--- a/lib/src/resource.dart
+++ b/lib/src/resource.dart
@@ -2,10 +2,35 @@
 // 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.
 
+/// A [Resource] is data that can be read into a Dart program.
+///
+/// A resource is identified by a URI. It can be loaded as bytes or data.
+/// The resource URI may be a `package:` URI.
+///
+/// Example:
+///
+///     var resource = new Resource("package:foo/foo_data.txt");
+///     var string = await resource.readAsString(UTF8);
+///     print(string);
+///
+/// Example:
+///
+///     var resource = new Resource("http://example.com/data.json");
+///     var obj = await resource.openRead()   // Reads as stream of bytes.
+///                             .transform(UTF8.fuse(JSON).decoder)
+///                             .first;
+///
+///
+/// Notice: Currently this package requires `dart:io` to do the reading,
+/// so it doesn't work in the browser.

[floitsch, 2016/01/21 12:53:57]

Mention the browser version.

[Lasse Reichstein Nielsen, 2016/01/25 10:48:37]

Done.

+library resource;
+
 import "dart:async" show Future, Stream;
-import "dart:convert" show Encoding;
-import "dart:isolate" show Isolate;
-import "loader.dart";
+
+import "loader.dart" show ResourceLoader;
+// TODO(lrn): Merge with implementation when configured imports removes
+// the need to share code.
+import "resource_impl.dart" as impl show Resource;
 
 /// A resource that can be read into the program.
 ///
@@ -13,7 +38,7 @@ import "loader.dart";
 /// the program at runtime.
 /// The URI may use the `package` scheme to read resources provided
 /// along with package sources.
-abstract class Resource {
+class Resource extends impl.Resource {
   /// Creates a resource object with the given [uri] as location.
   ///
   /// The [uri] must be either a [Uri] or a string containing a valid URI.
@@ -33,7 +58,8 @@ abstract class Resource {
   /// If [loader] is omitted, a default implementation is used which supports
   /// as many of `http`, `https`, `file` and `data` as are available on the
   /// current platform.
-  const factory Resource(uri, {ResourceLoader loader}) = _Resource;
+  const Resource(uri, {ResourceLoader loader})
+      : super(uri, (loader != null) ? loader : const DefaultLoader());
 
   /// The location URI of this resource.
   ///
@@ -54,34 +80,3 @@ abstract class Resource {
   /// If no other encoding is provided, it defaults to UTF-8.
   Future<String> readAsString({Encoding encoding});
 }
-
-class _Resource implements Resource {
-  /// Loading strategy for the resource.
-  final ResourceLoader _loader;
-
-  /// The URI of the resource.
-  final _uri;
-
-  const _Resource(uri, {ResourceLoader loader})
-      : _uri = uri, _loader = (loader != null) ? loader : const DefaultLoader();
-  // TODO: Make this `loader ?? const DefaultLoader()` when ?? is const.
-
-  Uri get uri => (_uri is String) ? Uri.parse(_uri) : (_uri as Uri);
-
-  Stream<List<int>> openRead() async* {
-    Uri uri = await _resolvedUri;
-    yield* _loader.openRead(uri);
-  }
-
-  Future<List<int>> readAsBytes() async {
-    Uri uri = await _resolvedUri;
-    return _loader.readAsBytes(uri);
-  }
-
-  Future<String> readAsString({Encoding encoding}) async {
-    Uri uri = await _resolvedUri;
-    return _loader.readAsString(uri, encoding: encoding);
-  }
-
-  Future<Uri> get _resolvedUri => resolveUri(uri);
-}