Don't use [operator==] to refer to [==] in DartDoc. It doesn't work.

sdk/lib/core/string.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;
 
 /**
  * A sequence of characters.
  *
  * A string can be either single or multiline. Single line strings are
@@ skipping 169 matching lines @@
    *
    *     var clef = '\u{1D11E}';
    *     clef.length;            // 2
    *     clef.runes.length;      // 1
    */
   int get length;
 
   /**
    * Returns a hash code derived from the code units of the string.
    *
-   * This is compatible with [operator==]. Strings with the same sequence
+   * This is compatible with [==]. Strings with the same sequence
    * of code units have the same hash code.
    */
   int get hashCode;
 
   /**
    * Returns true if other is a `String` with the same sequence of code units.
    *
    * This method compares each individual code unit of the strings.
    * It does not check for Unicode equivalence.
    * For example, both the following strings represent the string 'Amélie',
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         _position = position - 1;
         _currentCodePoint = _combineSurrogatePair(prevCodeUnit, codeUnit);
         return true;
       }
     }
     _position = position;
     _currentCodePoint = codeUnit;
     return true;
   }
 }