Support compiling templates in the browser.

lib/src/template/utils.dart

 // Copyright (c) 2012, 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.
 
 library utils;
 import 'package:web_components/src/template/world.dart';
 
 /**
  * Converts a string name with hyphens into an identifier, by removing hyphens
  * and capitalizing the following letter.
  */
 String toCamelCase(String hyphenedName) {
   var segments = hyphenedName.split('-');
   for (int i = 1; i < segments.length; i++) {
     var segment = segments[i];
     if (segment.length > 0) {
       // Character between 'a'..'z' mapped to 'A'..'Z'
       segments[i] = '${segment[0].toUpperCase()}${segment.substring(1)}';
     }
   }
   return Strings.join(segments, '');
 }
 
 /**
  * Invokes [callback], logs how long it took to execute in ms, and returns
  * whatever [callback] returns. The log message will be printed if either
  * [:options.showInfo:] or [printTime] are true.
  */
-time(String logMessage, callback(), [bool printTime = false]) {
+time(String logMessage, callback(), {bool printTime: false}) {
   final watch = new Stopwatch();
   watch.start();
   var result = callback();
   watch.stop();
   final duration = watch.elapsedInMs();
   if (options.showInfo || printTime) {
     print('$logMessage in $GREEN_COLOR$duration ms$NO_COLOR');
   }
   return result;
 }
 
+/**
+ *  Invokes [callback], logs how long it takes from the moment [callback] is
+ *  executed until the future it returns is completed. Returns the future
+ *  returned by [callback]. The log message will be printed if either
+ *  [:options.showInfo:] or [printTime] are true.
+ */
+Future asyncTime(String logMessage, Future callback(),
+                 {bool printTime: false}) {
+  final watch = new Stopwatch();
+  watch.start();
+  return callback()..then((_) {
+    watch.stop();
+    final duration = watch.elapsedInMs();
+    if (options.showInfo || printTime) {
+      print('$logMessage in $GREEN_COLOR$duration ms$NO_COLOR');
+    }
+  });
+}
+
 // Color constants used for generating messages.
 final String GREEN_COLOR = '\u001b[32m';
 final String RED_COLOR = '\u001b[31m';
 final String MAGENTA_COLOR = '\u001b[35m';
 final String NO_COLOR = '\u001b[0m';
 
 /** Find and return the first element in [list] that satisfies [matcher]. */
 find(List list, bool matcher(elem)) {
   for (var elem in list) {
     if (matcher(elem)) return elem;
   }
   return null;
 }