Improve type information and minor clean up

pkg/analyzer/lib/dart/element/element.dart

 // Copyright (c) 2014, 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.
 
 /**
  * Defines the element model. The element model describes the semantic (as
  * opposed to syntactic) structure of Dart code. The syntactic structure of the
  * code is modeled by the [AST structure](../ast/ast.dart).
  *
  * The element model consists of two closely related kinds of objects: elements
@@ skipping 739 matching lines @@
    *
    * <b>Note:</b> This method cannot be used in an async environment.
    */
   AstNode computeNode();
 
   /**
    * Return the most immediate ancestor of this element for which the
    * [predicate] returns `true`, or `null` if there is no such ancestor. Note
    * that this element will never be returned.
    */
-  Element getAncestor(Predicate<Element> predicate);
+  Element/*=E*/ getAncestor/*<E extends Element >*/(
+      Predicate<Element> predicate);
 
   /**
    * Return a display name for the given element that includes the path to the
    * compilation unit in which the type is defined. If [shortName] is `null`
    * then [getDisplayName] will be used as the name of this element. Otherwise
    * the provided name will be used.
    */
   // TODO(brianwilkerson) Make the parameter optional.
   String getExtendedDisplayName(String shortName);
 
@@ skipping 28 matching lines @@
 
   /**
    * Return a representation of the value of this annotation.
    *
    * Return `null` if the value of this annotation could not be computed because
    * of errors.
    */
   DartObject get constantValue;
 
   /**
-   * Return a representation of the value of this annotation, forcing the value
-   * to be computed if it had not previously been computed, or `null` if the
-   * value of this annotation could not be computed because of errors.
-   */
-  DartObject computeConstantValue();
-
-  /**
    * Return the element representing the field, variable, or const constructor
    * being used as an annotation.
    */
   Element get element;
 
   /**
    * Return `true` if this annotation marks the associated element as being
    * deprecated.
    */
   bool get isDeprecated;
@@ skipping 26 matching lines @@
    * Return `true` if this annotation marks the associated class as implementing
    * a proxy object.
    */
   bool get isProxy;
 
   /**
    * Return `true` if this annotation marks the associated member as being
    * required.
    */
   bool get isRequired;
+
+  /**
+   * Return a representation of the value of this annotation, forcing the value
+   * to be computed if it had not previously been computed, or `null` if the
+   * value of this annotation could not be computed because of errors.
+   */
+  DartObject computeConstantValue();
 }
 
 /**
  * The enumeration `ElementKind` defines the various kinds of elements in the
  * element model.
  *
  * Clients may not extend, implement or mix-in this class.
  */
 class ElementKind extends Enum<ElementKind> {
   static const ElementKind CLASS = const ElementKind('CLASS', 0, "class");
@@ skipping 1059 matching lines @@
   /**
    * Return a representation of the value of this variable.
    *
    * Return `null` if either this variable was not declared with the 'const'
    * modifier or if the value of this variable could not be computed because of
    * errors.
    */
   DartObject get constantValue;
 
   /**
-   * Return a representation of the value of this variable, forcing the value
-   * to be computed if it had not previously been computed, or `null` if either
-   * this variable was not declared with the 'const' modifier or if the value of
-   * this variable could not be computed because of errors.
-   */
-  DartObject computeConstantValue();
-
-  /**
    * Return `true` if this variable element did not have an explicit type
    * specified for it.
    */
   bool get hasImplicitType;
 
   /**
    * Return a synthetic function representing this variable's initializer, or
    * `null` if this variable does not have an initializer. The function will
    * have no parameters. The return type of the function will be the
    * compile-time type of the initialization expression.
@@ skipping 50 matching lines @@
    * > implicitly static.
    */
   bool get isStatic;
 
   /**
    * Return the declared type of this variable, or `null` if the variable did
    * not have a declared type (such as if it was declared using the keyword
    * 'var').
    */
   DartType get type;
+
+  /**
+   * Return a representation of the value of this variable, forcing the value
+   * to be computed if it had not previously been computed, or `null` if either
+   * this variable was not declared with the 'const' modifier or if the value of
+   * this variable could not be computed because of errors.
+   */
+  DartObject computeConstantValue();
 }