Rename blahHandler to onBlah throughout dart:io.

runtime/bin/directory.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.
 
 /**
  * [Directory] objects are used for working with directories.
  */
 interface Directory default _Directory {
   /**
    * Creates a directory object. The path is either a full path or
    * relative to the directory in which the Dart VM was
    * started.
    */
   Directory(String path);
 
   /**
    * Check whether a directory with this name already exists. If the
-   * operation completes successfully the [existsHandler] is called with
-   * the result. Otherwise the [errorHandler] is called.
+   * operation completes successfully the callback is called with the
+   * result. Otherwise [onError] is called.
    */
-  void exists();
+  void exists(void callback(bool exists));
 
   /**
    * Synchronously check whether a directory with this name already exists.
    */
   bool existsSync();
 
   /**
-   * Creates the directory with this name if it does not exist.
-   * If the directory is successfully created the [createHandler] is
-   * called. Otherwise the [errorHandler] is called.
+   * Creates the directory with this name if it does not exist.  If
+   * the directory is successfully created the callback is
+   * called. Otherwise [onError] is called.
    */
-  void create();
+  void create(void callback());
 
   /**
    * Synchronously creates the directory with this name if it does not exist.
    * Throws an exception if the directory already exists.
    */
   void createSync();
 
   /**
-   * Creates a temporary directory with a name based on the current path.
-   * This name and path is used as a template, and additional characters are
-   * appended to it by the call to make a unique directory name.  If the
-   * path is the empty string, a default system temp directory and name
-   * are used for the template.
-   * The path is modified to be the path of the new directory.
-   * After the new directory is created, and the path modified, the callback
-   * createTempHandler will be called.  The error handler is called if
-   * the temporary directory cannot be created.
+   * Creates a temporary directory with a name based on the current
+   * path.  This name and path is used as a template, and additional
+   * characters are appended to it by the call to make a unique
+   * directory name.  If the path is the empty string, a default
+   * system temp directory and name are used for the template.
+   *
+   * The path is modified to be the path of the new directory.  After
+   * the new directory is created, and the path modified, the callback
+   * will be called.  The error handler is called if the temporary
+   * directory cannot be created.
    */
-  void createTemp();
+  void createTemp(void callback());
 
   /**
    * Synchronously creates a temporary directory with a name based on the
    * current path. This name and path is used as a template, and additional
    * characters are appended to it by the call to make a unique directory name.
    * If the path is the empty string, a default system temp directory and name
    * are used for the template.
    * The path is modified to be the path of the new directory.
    */
   void createTempSync();
 
   /**
-   * Deletes the directory with this name. If the operation completes
-   * successfully the [deleteHandler] is called. Otherwise the
-   * [errorHandler] is called.
-   *
-   * If [recursive] is [:true:] this directory and all sub-directories
-   * and files in the directory are deleted. If [recursive] is
-   * [:false:] only this directory (which must be empty) is
-   * deleted. [recursive] is [:false:] by default.
+   * Deletes the directory with this name. The directory must be
+   * empty. If the operation completes successfully the callback is
+   * called. Otherwise [onError] is called.
    */
-  void delete([bool recursive]);
+  void delete(void callback());
 
   /**
-   * Deletes the directory with this name. Throws an exception
-   * if the directory cannot be deleted.
-   *
-   * If [recursive] is [:true:] this directory and all sub-directories
-   * and files in the directory are deleted. If [recursive] is
-   * [:false:] only this directory (which must be empty) is
-   * deleted. [recursive] is [:false:] by default.
+   * Deletes this directory and all sub-directories and files in the
+   * directories. If the operation completes successfully the callback
+   * is called. Otherwise [onError] is called.
    */
-  void deleteSync([bool recursive]);
+  void deleteRecursively(void callback());
+
+  /**
+   * Synchronously deletes the directory with this name. The directory
+   * must be empty. Throws an exception if the directory cannot be
+   * deleted.
+   */
+  void deleteSync();
+
+  /**
+   * Synchronously deletes this directory and all sub-directories and
+   * files in the directories. Throws an exception if the directory
+   * cannot be deleted.
+   */
+  void deleteRecursivelySync();
 
   /**
    * List the sub-directories and files of this
    * [Directory]. Optionally recurse into sub-directories. For each
    * file and directory, the file or directory handler is called. When
    * all directories have been listed the done handler is called. If
    * the listing operation is recursive, the error handler is called
    * if a subdirectory cannot be opened for listing.
    */
+  // TODO(ager): Should we change this to return an event emitting
+  // DirectoryLister object. Alternatively, pass in one callback that
+  // gets called with an indication of whether what it is called with
+  // is a file, a directory or an indication that the listing is over.
   void list([bool recursive]);
 
   /**
    * Sets the directory handler that is called for all directories
    * during listing operations. The directory handler is called with
    * the full path of the directory.
    */
-  void set dirHandler(void dirHandler(String dir));
+  void set onDir(void onDir(String dir));
 
   /**
    * Sets the handler that is called for all files during listing
    * operations. The file handler is called with the full path of the
    * file.
    */
-  void set fileHandler(void fileHandler(String file));
+  void set onFile(void onFile(String file));
 
   /**
    * Set the handler that is called when a directory listing is
    * done. The handler is called with an indication of whether or not
    * the listing operation completed.
    */
-  void set doneHandler(void doneHandler(bool completed));
-
-  /**
-   * Set the handler that is called when checking if a directory with this
-   * name exists.
-   */
-  void set existsHandler(void existsHandler(bool exists));
-
-  /**
-   * Set the handler that is called when a directory is successfully created.
-   */
-  void set createHandler(void createHandler());
-
-  /**
-   * Set the handler that is called when a temporary directory is
-   * successfully created.
-   */
-  void set createTempHandler(void createTempHandler());
-
-  /**
-   * Set the handler that is called when a directory is successfully
-   * deleted.
-   */
-  void set deleteHandler(void deleteHandler());
+  void set onDone(void onDone(bool completed));
 
   /**
    * Sets the handler that is called if there is an error while listing
    * or creating directories.
    */
-  void set errorHandler(void errorHandler(String error));
+  void set onError(void onError(String error));
 
   /**
    * Gets the path of this directory.
    */
   final String path;
 }
 
 
 class DirectoryException {
   const DirectoryException([String this.message, int this.errorCode = 0]);
   String toString() => "DirectoryException: $message";
   final String message;
   final int errorCode;
 }