Add num.parse.

sdk/lib/core/int.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.
 
 part of dart.core;
 
 /**
  * An arbitrarily large integer.
  *
  * **Note:** When compiling to JavaScript, integers are
@@ skipping 228 matching lines @@
    */
   String toRadixString(int radix);
 
   /**
    * Parse [source] as an integer literal and return its value.
    *
    * The [radix] must be in the range 2..36. The digits used are
    * first the decimal digits 0..9, and then the letters 'a'..'z'.
    * Accepts capital letters as well.
    *
    * If no [radix] is given then it defaults to 16 if the string starts

[floitsch, 2013/11/25 12:50:53]

.. it defaults to 10, unless the string starts with "0x", "-0x" or "+0x" in
which case radix is set to "16" and the "0x" is ignored.

?

[Lasse Reichstein Nielsen, 2013/11/25 13:05:16]

Sounds much better. Done!

-   * with "0x", "-0x" or "+0x" and 10 otherwise.
+   * with "0x", "-0x" or "+0x" (and the "0x" is then ignored) and 10 otherwise.
    *
    * The [source] must be a non-empty sequence of base-[radix] digits,
    * optionally prefixed with a minus or plus sign ('-' or '+').
    *
    * It must always be the case for an int [:n:] and radix [:r:] that
    * [:n == parseRadix(n.toRadixString(r), r):].
    *
    * If the [source] is not a valid integer literal, optionally prefixed by a
    * sign, the [onError] is called with the [source] as argument, and its return
    * value is used instead. If no [onError] is provided, a [FormatException]
    * is thrown.
    *
    * The [onError] function is only invoked if [source] is a [String]. It is
    * not invoked if the [source] is, for example, `null`.
    */
   external static int parse(String source,
                             { int radix,
                               int onError(String source) });
 }