Use iterator, moveNext(), current.

runtime/lib/string_base.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.
 
 /**
  * [_StringBase] contains common methods used by concrete String
  * implementations, e.g., _OneByteString.
  */
 class _StringBase {
 
@@ skipping 171 matching lines @@
       return this;
     } else {
       return _substringUnchecked(first, last + 1);
     }
   }
 
   bool contains(Pattern pattern, [int startIndex = 0]) {
     if (pattern is String) {
       return indexOf(pattern, startIndex) >= 0;
     }
-    return pattern.allMatches(this.substring(startIndex)).iterator().hasNext;
+    return pattern.allMatches(this.substring(startIndex)).iterator.moveNext();
   }
 
   String replaceFirst(Pattern pattern, String replacement) {
     if (pattern is! Pattern) {
       throw new ArgumentError("${pattern} is not a Pattern");
     }
     if (replacement is! String) {
       throw new ArgumentError("${replacement} is not a String");
     }
     StringBuffer buffer = new StringBuffer();
     int startIndex = 0;
-    Iterator iterator = pattern.allMatches(this).iterator();
-    if (iterator.hasNext) {
-      Match match = iterator.next();
+    Iterator iterator = pattern.allMatches(this).iterator;
+    if (iterator.moveNext()) {
+      Match match = iterator.current;
       buffer.add(this.substring(startIndex, match.start)).add(replacement);
       startIndex = match.end;
     }
     return buffer.add(this.substring(startIndex)).toString();
   }
 
   String replaceAll(Pattern pattern, var replacement) {
     if (pattern is! Pattern) {
       throw new ArgumentError("${pattern} is not a Pattern");
     }
@@ skipping 56 matching lines @@
         ++startIndex;  // empty match, advance and restart
       } else {
         startIndex = endIndex;
       }
     }
     return result;
   }
 
   List<String> split(Pattern pattern) {
     int length = this.length;
-    Iterator iterator = pattern.allMatches(this).iterator();
-    if (length == 0 && iterator.hasNext) {
+    Iterator iterator = pattern.allMatches(this).iterator;
+    if (length == 0 && iterator.moveNext()) {
       // A matched empty string input returns the empty list.
       return <String>[];
     }
     List<String> result = new List<String>();
     int startIndex = 0;
     int previousIndex = 0;
     while (true) {
-      if (startIndex == length || !iterator.hasNext) {
+      if (startIndex == length || !iterator.moveNext()) {
         result.add(this.substring(previousIndex, length));
         break;
       }
-      Match match = iterator.next();
+      Match match = iterator.current;
       if (match.start == length) {
         result.add(this.substring(previousIndex, length));
         break;
       }
       int endIndex = match.end;
       if (startIndex == endIndex && endIndex == previousIndex) {
         ++startIndex;  // empty match, advance and restart
         continue;
       }
       result.add(this.substring(previousIndex, match.start));
@@ skipping 187 matching lines @@
     for (int g in groups) {
       result.add(group(g));
     }
     return result;
   }
 
   final int start;
   final String str;
   final String pattern;
 }