Use VM type cast and save handles.

runtime/vm/debugger_api_impl.cc

 // 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.
 
 #include "include/dart_debugger_api.h"
 
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/debugger.h"
 #include "vm/isolate.h"
 #include "vm/object_store.h"
 
 namespace dart {
 
 #define UNWRAP_AND_CHECK_PARAM(type, var, param)                              \
   do {                                                                        \
     const Object& tmp = Object::Handle(Api::UnwrapHandle(param));             \
     if (tmp.IsNull()) {                                                       \
       return Api::NewError("%s expects argument '%s' to be non-null.",        \
                            CURRENT_FUNC, #param);                             \
     } else if (tmp.IsApiError()) {                                            \
       return param;                                                           \
     } else if (!tmp.Is##type()) {                                             \
       return Api::NewError("%s expects argument '%s' to be of type %s.",      \
                            CURRENT_FUNC, #param, #type);                      \
     }                                                                         \
     var ^= tmp.raw();                                                         \
-  } while (0);
+  } while (0)

[Ivan Posva, 2012/07/02 21:01:38]

Why here, but not below in CHECK_AND_CAST?

[regis, 2012/07/02 21:42:33]

You would have to ask Matthias :-)
Now wrapped in do while(0) and moved line continuation slashes to column 80.
I also moved the var declaration from the use location to inside the macro.

 
 
 #define CHECK_AND_CAST(type, var, param)                                      \
   if (param == NULL) {                                                        \
     return Api::NewError("%s expects argument '%s' to be non-null.",          \
                          CURRENT_FUNC, #param);                               \
   }                                                                           \
   type* var = reinterpret_cast<type*>(param);
 
 
@@ skipping 626 matching lines @@
   for (int i = 0; i < num_libs; i++) {
     lib ^= libs.At(i);
     ASSERT(!lib.IsNull());
     lib_url = lib.url();
     library_url_list.SetAt(i, lib_url);
   }
   return Api::NewHandle(isolate, library_url_list.raw());
 }
 
 }  // namespace dart