Report arity errors on user definable operators.

sdk/lib/_internal/compiler/implementation/warnings.dart

 // Copyright (c) 2011, 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 dart2js;
 
 class MessageKind {
   final String template;
   const MessageKind(this.template);
 
@@ skipping 240 matching lines @@
 
   static const BAD_ARITY_OVERRIDE_CONT = const MessageKind(
       "Info: this is the method whose parameters do not match.");
 
   static const MISSING_FORMALS = const MessageKind(
       "Error: Formal parameters are missing.");
 
   static const EXTRA_FORMALS = const MessageKind(
       "Error: Formal parameters are not allowed here.");
 
+  static const UNARY_OPERATOR_BAD_ARITY = const MessageKind(
+      "Error: Operator #{1} must have no parameters.");
+
+  static const MINUS_OPERATOR_BAD_ARITY = const MessageKind(
+      "Error: Operator - must have 0 or 1 parameters.");
+
+  static const BINARY_OPERATOR_BAD_ARITY = const MessageKind(
+      "Error: Operator #{1} must have exactly 1 parameter.");
+
+  static const TERNARY_OPERATOR_BAD_ARITY = const MessageKind(
+      "Error: Operator #{1} must have exactly 2 parameters.");
+
+  static const OPERATOR_OPTIONAL_PARAMETERS = const MessageKind(
+      "Error: Operator #{1} cannot have optional parameters.");
+
+  static const OPERATOR_NAMED_PARAMETERS = const MessageKind(
+      "Error: Operator #{1} cannot have named parameters.");
+
   // TODO(ahe): This message is hard to localize.  This is acceptable,
   // as it will be removed when we ship Dart version 1.0.
   static const DEPRECATED_FEATURE_WARNING = const MessageKind(
       "Warning: deprecated language feature, #{1}, "
       "will be removed in a future Dart milestone.");
 
   // TODO(ahe): This message is hard to localize.  This is acceptable,
   // as it will be removed when we ship Dart version 1.0.
   static const DEPRECATED_FEATURE_ERROR = const MessageKind(
       "Error: #{1} are not legal "
@@ skipping 171 matching lines @@
 
 class CompileTimeConstantError extends Diagnostic {
   CompileTimeConstantError(MessageKind kind, List arguments)
     : super(kind, arguments);
 }
 
 class CompilationError extends Diagnostic {
   CompilationError(MessageKind kind, List arguments)
     : super(kind, arguments);
 }