Revert "Make Comparable generic."

This reverts commit dd714db881a0ad63eaa1e5491e93dd8843eb5929.

R=lrn@google.com
BUG=

Review URL: https://codereview.chromium.org//12298027

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@18657 260f80e4-7a28-3924-810f-c04153c831b5

pkg/fixnum/lib/src/int32.dart

@@ -288,7 +288,7 @@ class int32 implements intx {
     return _i == _convert(other);
   }
 
-  int compareTo(other) {
+  int compareTo(Comparable other) {
     if (other is int64) {
       return this.toInt64().compareTo(other);
     }

pkg/logging/lib/logging.dart

@@ -247,7 +247,7 @@ class LoggerHandlerList {
  * own level, make sure you use a value between those used in [Level.ALL] and
  * [Level.OFF].
  */
-class Level implements Comparable<Level> {
+class Level implements Comparable {
 
   // TODO(sigmund): mark name/value as 'const' when the language supports it.
   final String name;

pkg/serialization/lib/src/basic_rule.dart

@@ -271,7 +271,7 @@ class BasicRule extends SerializationRule {
  * This represents a field in an object. It is intended to be used as part of
  * a [_FieldList].
  */
-abstract class _Field implements Comparable<_Field> {
+abstract class _Field implements Comparable {
 
   /** The FieldList that contains us. */
   final _FieldList fieldList;

sdk/lib/collection/splay_tree.dart

@@ -26,7 +26,7 @@ class SplayTreeNode<K, V> {
  * This implementation is a Dart version of the JavaScript
  * implementation in the V8 project.
  */
-class SplayTreeMap<K extends Comparable<K>, V> implements Map<K, V> {
+class SplayTreeMap<K extends Comparable, V> implements Map<K, V> {
 
   // The root node of the splay tree. It will contain either the last
   // element inserted, or the last element looked up.

sdk/lib/core/comparable.dart

@@ -22,7 +22,7 @@ typedef int Comparator<T>(T a, T b);
 /**
  * Interface used by types that have an intrinsic ordering.
  */
-abstract class Comparable<T extends Comparable<T>> {
+abstract class Comparable {
   /**
    * Compares this object to another [Comparable]
    *
@@ -31,7 +31,7 @@ abstract class Comparable<T extends Comparable<T>> {
    * May throw an [ArgumentError] if [other] is of a type that
    * is not comparable to [:this:].
    */
-  int compareTo(T other);
+  int compareTo(Comparable other);
 
   /**
    * Compare one comparable to another.

sdk/lib/core/date_time.dart

@@ -8,7 +8,7 @@ part of dart.core;
  * Deprecated class. Please use [DateTime] instead.
  */
 @deprecated
-abstract class Date implements Comparable<Date> {
+abstract class Date implements Comparable {
   // Weekday constants that are returned by [weekday] method:
   static const int MON = 1;
   static const int TUE = 2;

sdk/lib/core/num.dart

@@ -7,7 +7,7 @@ part of dart.core;
 /**
  * All numbers in dart are instances of [num].
  */
-abstract class num implements Comparable<num> {
+abstract class num implements Comparable {
   /** Addition operator. */
   num operator +(num other);
 

utils/css/source.dart

@@ -6,7 +6,7 @@
 /**
  * Represents a file of source code.
  */
-class SourceFile implements Comparable<SourceFile> {
+class SourceFile implements Comparable {
   // TODO(terry): This filename for in memory buffer.  May need to rework if
   //              filename is used for more than informational.
   static String IN_MEMORY_FILE = '<buffer>';
@@ -132,7 +132,7 @@ class SourceFile implements Comparable<SourceFile> {
  * work.
  */
  // TODO(jmesserly): Rename to Span - but first write cool refactoring tool
-class SourceSpan implements Comparable<SourceSpan> {
+class SourceSpan implements Comparable {
   /** The [SourceFile] that contains this span. */
   final SourceFile file;
 

utils/pub/package.dart

@@ -85,7 +85,7 @@ class Package {
 /// different directories that happen to contain identical packages. For
 /// example, the same package may be available from multiple sources. As far as
 /// Pub is concerned, those packages are different.
-class PackageId implements Comparable<PackageId> {
+class PackageId implements Comparable {
   /// The name of the package being identified.
   final String name;
 
@@ -129,7 +129,9 @@ class PackageId implements Comparable<PackageId> {
     return "$name $version from $source";
   }
 
-  int compareTo(PackageId other) {
+  int compareTo(Comparable other) {
+    if (other is! PackageId) throw new ArgumentError(other);
+
     var sourceComp = source.name.compareTo(other.source.name);
     if (sourceComp != 0) return sourceComp;
 

utils/template/source.dart

@@ -6,7 +6,7 @@
 /**
  * Represents a file of source code.
  */
-class SourceFile implements Comparable<SourceFile> {
+class SourceFile implements Comparable {
   // TODO(terry): This filename for in memory buffer.  May need to rework if
   //              filename is used for more than informational.
   static String IN_MEMORY_FILE = '<buffer>';
@@ -132,7 +132,7 @@ class SourceFile implements Comparable<SourceFile> {
  * work.
  */
  // TODO(jmesserly): Rename to Span - but first write cool refactoring tool
-class SourceSpan implements Comparable<SourceSpan> {
+class SourceSpan implements Comparable {
   /** The [SourceFile] that contains this span. */
   final SourceFile file;