Pass handles not raw objects into methods.

runtime/vm/dart_entry.h

 // 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.
 
 #ifndef VM_DART_ENTRY_H_
 #define VM_DART_ENTRY_H_
 
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
 
 namespace dart {
 
 // Forward declarations.
 class Array;
 class Closure;
 class Context;
 class Function;
 class Instance;
 class Integer;
 class Library;
 class Object;
 class RawArray;
 class RawInstance;
 class RawObject;
+class RawString;
 class String;
 
 // An arguments descriptor array consists of the total argument count; the
 // positional argument count; a sequence of (name, position) pairs, sorted
 // by name, for each named optional argument; and a terminating null to
 // simplify iterating in generated code.
 class ArgumentsDescriptor : public ValueObject {
  public:
-  explicit ArgumentsDescriptor(RawObject* array);
+  explicit ArgumentsDescriptor(const Array& array);
 
   // Accessors.
   intptr_t Count() const;
   intptr_t PositionalCount() const;
   intptr_t NamedCount() const { return Count() - PositionalCount(); }
-  RawObject* NameAt(intptr_t index) const;
+  RawString* NameAt(intptr_t index) const;
 
   // Generated code support.
   static intptr_t count_offset();
   static intptr_t positional_count_offset();
   static intptr_t first_named_entry_offset();
   static intptr_t name_offset() { return kNameOffset * kWordSize; }
   static intptr_t position_offset() { return kPositionOffset * kWordSize; }
   static intptr_t named_entry_size() { return kNamedEntrySize * kWordSize; }
 
   // Allocate and return an arguments descriptor.  The first
@@ skipping 16 matching lines @@
     kPositionOffset,
     kNamedEntrySize,
   };
 
   static intptr_t LengthFor(intptr_t count) {
     // Add 1 for the terminating null.
     return kFirstNamedEntryIndex + (kNamedEntrySize * count) + 1;
   }
 
   const Array& array_;
+
+  DISALLOW_COPY_AND_ASSIGN(ArgumentsDescriptor);
 };
 
 
 // DartEntry abstracts functionality needed to resolve dart functions
 // and invoke them from C++.
 class DartEntry : public AllStatic {
  public:
   // On success, returns a RawInstance.  On failure, a RawError.
   typedef RawObject* (*invokestub)(uword entry_point,
                                    const Array& arguments_descriptor,
@@ skipping 57 matching lines @@
 
   // Gets the _id field of a SendPort/ReceivePort.
   //
   // Returns the value of _id on success, a RawError on failure.
   static RawObject* PortGetId(const Instance& port);
 };
 
 }  // namespace dart
 
 #endif  // VM_DART_ENTRY_H_