Rewrite double.parse.

runtime/lib/integers_patch.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.
 // Dart core library.
 
 // VM implementation of int.
 
 patch class int {
 
-  static bool _isWhitespace(int codePoint) {
-    return
-      (codePoint == 32) || // Space.
-      ((9 <= codePoint) && (codePoint <= 13)); // CR, LF, TAB, etc.
-  }
-
   static int _tryParseSmi(String str) {
     if (str.isEmpty) return null;
     var ix = 0;
     var endIx = str.length - 1;
     // Find first and last non-whitespace.
     while (ix <= endIx) {
-      if (!_isWhitespace(str.codeUnitAt(ix))) break;
+      if (!str._isWhitespace(str.codeUnitAt(ix))) break;

[Lasse Reichstein Nielsen, 2013/05/21 06:12:09]

This is a hack that deserves explanation. 
Anybody would expect _isWhitespace to be static/top-level here.
Is this really faster than using the same function all the time, and starting it
with a (unit <= 127) branch?

Assign str to a dynamic variable before doing this call. It should generate a
warning, since _isWhiteSpace is not on the String class.

[floitsch, 2013/05/21 14:39:31]

Has been removed.

       ix++;
     }
     if (endIx < ix) {
       return null;  // Empty.
     }
     while (endIx > ix) {
-      if (!_isWhitespace(str.codeUnitAt(endIx))) break;
+      if (!str._isWhitespace(str.codeUnitAt(endIx))) break;
       endIx--;
     }
 
     var isNegative = false;
     var c = str.codeUnitAt(ix);
     // Check for leading '+' or '-'.
     if ((c == 0x2b) || (c == 0x2d)) {
       ix++;
       isNegative = (c == 0x2d);
       if (ix > endIx) {
@@ skipping 83 matching lines @@
       int digit = digits[code - 0x30];
       if (digit >= radix) return onError(source);
       result = result * radix + digit;
       i++;
       if (i == source.length) break;
       code = source.codeUnitAt(i);
     } while (true);
     return negative ? -result : result;
   }
 }