Refactor the dart api a bit:

runtime/vm/dart_api_impl_test.cc

 // 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.
 
 #include "include/dart_api.h"
 
 #include "vm/assert.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/unit_test.h"
 #include "vm/utils.h"
 #include "vm/verifier.h"
 
 namespace dart {
 
 UNIT_TEST_CASE(BooleanValues) {
   Dart_CreateIsolate(NULL, NULL);
   Dart_EnterScope();  // Enter a Dart API scope for the unit test.
 
   Dart_Handle str = Dart_NewString("test");
   EXPECT(!Dart_IsBoolean(str));
   Dart_Handle val1 = Dart_NewBoolean(true);
   EXPECT(Dart_IsBoolean(val1));
   Dart_Handle val2 = Dart_NewBoolean(false);
   EXPECT(Dart_IsBoolean(val2));
-  Dart_Result result = Dart_BooleanValue(val1);
-  EXPECT(Dart_IsValidResult(result) && Dart_GetResultAsCBoolean(result));
-  result = Dart_BooleanValue(val2);
-  EXPECT(Dart_IsValidResult(result) && !Dart_GetResultAsCBoolean(result));
+  bool value = false;
+  Dart_Handle result = Dart_BooleanValue(val1, &value);
+  EXPECT(Dart_IsValid(result) && value);
+  result = Dart_BooleanValue(val2, &value);
+  EXPECT(Dart_IsValid(result) && !value);
 
   Dart_ExitScope();  // Exit the Dart API scope.
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(DoubleValues) {
   Dart_CreateIsolate(NULL, NULL);
   Dart_EnterScope();  // Enter a Dart API scope for the unit test.
 
   const double kDoubleVal1 = 201.29;
   const double kDoubleVal2 = 101.19;
   Dart_Handle val1 = Dart_NewDouble(kDoubleVal1);
   EXPECT(Dart_IsDouble(val1));
   Dart_Handle val2 = Dart_NewDouble(kDoubleVal2);
   EXPECT(Dart_IsDouble(val2));
-  Dart_Result result = Dart_DoubleValue(val1);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT_EQ(kDoubleVal1, Dart_GetResultAsCDouble(result));
-  result = Dart_DoubleValue(val2);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT_EQ(kDoubleVal2, Dart_GetResultAsCDouble(result));
+  double out1, out2;
+  Dart_Handle result = Dart_DoubleValue(val1, &out1);
+  EXPECT(Dart_IsValid(result));
+  EXPECT_EQ(kDoubleVal1, out1);
+  result = Dart_DoubleValue(val2, &out2);
+  EXPECT(Dart_IsValid(result));
+  EXPECT_EQ(kDoubleVal2, out2);
 
   Dart_ExitScope();  // Exit the Dart API scope.
   Dart_ShutdownIsolate();
 }
 
 
 #if defined(TARGET_ARCH_IA32)  // only ia32 can run execution tests.
 
 UNIT_TEST_CASE(NumberValues) {
   // TODO(antonm): add various kinds of ints (smi, mint, bigint).
   const char* kScriptChars =
       "class NumberValuesHelper {\n"
       "  static int getInt() { return 1; }\n"
       "  static double getDouble() { return 1.0; }\n"
       "  static bool getBool() { return false; }\n"
       "  static getNull() { return null; }\n"
       "}\n";
-  Dart_Result result;
-  Dart_Handle handle;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     Dart_Handle class_name = Dart_NewString("NumberValuesHelper");
     // Check int case.
     result = Dart_InvokeStatic(lib,
                                class_name,
                                Dart_NewString("getInt"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    handle = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(handle));
-    EXPECT(Dart_IsNumber(handle));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(Dart_IsNumber(result));
 
     // Check double case.
     result = Dart_InvokeStatic(lib,
                                class_name,
                                Dart_NewString("getDouble"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    handle = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(handle));
-    EXPECT(Dart_IsNumber(handle));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(Dart_IsNumber(result));
 
     // Check bool case.
     result = Dart_InvokeStatic(lib,
                                class_name,
                                Dart_NewString("getBool"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    handle = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(handle));
-    EXPECT(!Dart_IsNumber(handle));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(!Dart_IsNumber(result));
 
     // Check null case.
     result = Dart_InvokeStatic(lib,
                                class_name,
                                Dart_NewString("getNull"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    handle = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(handle));
-    EXPECT(!Dart_IsNumber(handle));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(!Dart_IsNumber(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 #endif
 
 
 UNIT_TEST_CASE(IntegerValues) {
   Dart_CreateIsolate(NULL, NULL);
   Dart_EnterScope();  // Enter a Dart API scope for the unit test.
 
   const int64_t kIntegerVal1 = 100;
   const int64_t kIntegerVal2 = 0xffffffff;
   const char* kIntegerVal3 = "0x123456789123456789123456789";
 
   Dart_Handle val1 = Dart_NewInteger(kIntegerVal1);
   EXPECT(Dart_IsInteger(val1));
-  Dart_Result fits = Dart_IntegerFitsIntoInt64(val1);
-  EXPECT(Dart_IsValidResult(fits));
-  EXPECT(Dart_GetResultAsCBoolean(fits));
+  bool fits = false;
+  Dart_Handle result = Dart_IntegerFitsIntoInt64(val1, &fits);
+  EXPECT(Dart_IsValid(result));
+  EXPECT(fits);
 
   Dart_Handle val2 = Dart_NewInteger(kIntegerVal2);
   EXPECT(Dart_IsInteger(val2));
-  fits = Dart_IntegerFitsIntoInt64(val2);
-  EXPECT(Dart_IsValidResult(fits));
-  EXPECT(Dart_GetResultAsCBoolean(fits));
+  result = Dart_IntegerFitsIntoInt64(val2, &fits);
+  EXPECT(Dart_IsValid(result));
+  EXPECT(fits);
 
   Dart_Handle val3 = Dart_NewIntegerFromHexCString(kIntegerVal3);
   EXPECT(Dart_IsInteger(val3));
-  fits = Dart_IntegerFitsIntoInt64(val3);
-  EXPECT(Dart_IsValidResult(fits));
-  EXPECT(!Dart_GetResultAsCBoolean(fits));
+  result = Dart_IntegerFitsIntoInt64(val3, &fits);
+  EXPECT(Dart_IsValid(result));
+  EXPECT(!fits);
 
-  Dart_Result result = Dart_IntegerValue(val1);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT_EQ(kIntegerVal1, Dart_GetResultAsCInt64(result));
+  int64_t out = 0;
+  result = Dart_IntegerValue(val1, &out);
+  EXPECT(Dart_IsValid(result));
+  EXPECT_EQ(kIntegerVal1, out);
 
-  result = Dart_IntegerValue(val2);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT_EQ(kIntegerVal2, Dart_GetResultAsCInt64(result));
+  result = Dart_IntegerValue(val2, &out);
+  EXPECT(Dart_IsValid(result));
+  EXPECT_EQ(kIntegerVal2, out);
 
-  result = Dart_IntegerValue(val3);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT(!strcmp(kIntegerVal3, Dart_GetResultAsCString(result)));
+  const char* chars = NULL;
+  result = Dart_IntegerValueHexCString(val3, &chars);
+  EXPECT(Dart_IsValid(result));
+  EXPECT(!strcmp(kIntegerVal3, chars));
 
   Dart_ExitScope();  // Exit the Dart API scope.
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(ArrayValues) {
   Dart_CreateIsolate(NULL, NULL);
   Dart_EnterScope();  // Enter a Dart API scope for the unit test.
 
   const int kArrayLength = 10;
   Dart_Handle str = Dart_NewString("test");
   EXPECT(!Dart_IsArray(str));
   Dart_Handle val = Dart_NewArray(kArrayLength);
   EXPECT(Dart_IsArray(val));
-  Dart_Result result = Dart_GetLength(val);
-  EXPECT(Dart_IsValidResult(result));
-  EXPECT_EQ(kArrayLength, Dart_GetResultAsCIntptr(result));
+  intptr_t len = 0;
+  Dart_Handle result = Dart_GetLength(val, &len);
+  EXPECT(Dart_IsValid(result));
+  EXPECT_EQ(kArrayLength, len);
 
   // Check invalid array access.
   result = Dart_ArraySetAt(val, (kArrayLength + 10), Dart_NewInteger(10));
-  EXPECT(!Dart_IsValidResult(result));
+  EXPECT(!Dart_IsValid(result));
   result = Dart_ArraySetAt(val, -10, Dart_NewInteger(10));
-  EXPECT(!Dart_IsValidResult(result));
+  EXPECT(!Dart_IsValid(result));
   result = Dart_ArrayGetAt(val, (kArrayLength + 10));
-  EXPECT(!Dart_IsValidResult(result));
+  EXPECT(!Dart_IsValid(result));
   result = Dart_ArrayGetAt(val, -10);
-  EXPECT(!Dart_IsValidResult(result));
+  EXPECT(!Dart_IsValid(result));
 
   for (int i = 0; i < kArrayLength; i++) {
     result = Dart_ArraySetAt(val, i, Dart_NewInteger(i));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
   }
   for (int i = 0; i < kArrayLength; i++) {
     result = Dart_ArrayGetAt(val, i);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle val_obj = Dart_GetResult(result);
-    result = Dart_IntegerValue(val_obj);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT_EQ(i, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    int64_t value;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT(Dart_IsValid(result));
+    EXPECT_EQ(i, value);
   }
 
   Dart_ExitScope();  // Exit the Dart API scope.
   Dart_ShutdownIsolate();
 }
 
 
 // Unit test for entering a scope, creating a local handle and exiting
 // the scope.
 UNIT_TEST_CASE(EnterExitScope) {
@@ skipping 262 matching lines @@
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class FieldsTest {\n"
       "  static Fields testMain() {\n"
       "    Fields obj = new Fields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("FieldsTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("FieldsTest"),
+                                           Dart_NewString("testMain"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     // Now access and set various static fields of Fields class.
-    result = Dart_GetClass(lib, Dart_NewString("Fields"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle cls = Dart_GetResult(result);
+    Dart_Handle cls = Dart_GetClass(lib, Dart_NewString("Fields"));
+    EXPECT(Dart_IsValid(cls));
     result = Dart_GetStaticField(cls, Dart_NewString("fld1"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld3"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetStaticField(cls, Dart_NewString("fld4"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(10, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(10, value);
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("fld4"),
                                  Dart_NewInteger(20));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetStaticField(cls, Dart_NewString("fld3"));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("fld3"),
                                  Dart_NewInteger(200));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(200, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(200, value);
 
     // Now access and set various instance fields of the returned object.
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld3"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(10, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(10, value);
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(20, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(20, value);
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("fld2"),
                                    Dart_NewInteger(40));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("fld1"),
                                    Dart_NewInteger(40));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(40, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(40, value);
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(HiddenFieldAccess) {
   const char* kScriptChars =
       "class HiddenFields  {\n"
       "  HiddenFields(int i, int j) : _fld1 = i, _fld2 = j {}\n"
       "  int _fld1;\n"
       "  final int _fld2;\n"
       "  static int _fld3;\n"
       "  static final int _fld4 = 10;\n"
       "}\n"
       "class HiddenFieldsTest {\n"
       "  static HiddenFields testMain() {\n"
       "    HiddenFields obj = new HiddenFields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Load up a test script which extends the native wrapper class.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("HiddenFieldsTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("HiddenFieldsTest"),
+                                           Dart_NewString("testMain"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     // Now access and set various static fields of HiddenFields class.
-    result = Dart_GetClass(lib, Dart_NewString("HiddenFields"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle cls = Dart_GetResult(result);
+    Dart_Handle cls = Dart_GetClass(lib, Dart_NewString("HiddenFields"));
+    EXPECT(Dart_IsValid(cls));
     result = Dart_GetStaticField(cls, Dart_NewString("_fld1"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("_fld3"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetStaticField(cls, Dart_NewString("_fld4"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(10, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(10, value);
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("_fld4"),
                                  Dart_NewInteger(20));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetStaticField(cls, Dart_NewString("_fld3"));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("_fld3"),
                                  Dart_NewInteger(200));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(200, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(200, value);
 
     // Now access and set various instance fields of the returned object.
     result = Dart_GetInstanceField(retobj, Dart_NewString("_fld3"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("_fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(10, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(10, value);
     result = Dart_GetInstanceField(retobj, Dart_NewString("_fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(20, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(20, value);
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("_fld2"),
                                    Dart_NewInteger(40));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("_fld1"),
                                    Dart_NewInteger(40));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("_fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(40, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(40, value);
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(InjectNativeFields1) {
   const char* kScriptChars =
       "class NativeFields extends NativeFieldsWrapper {\n"
       "  NativeFields(int i, int j) : fld1 = i, fld2 = j {}\n"
       "  int fld1;\n"
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class NativeFieldsTest {\n"
       "  static NativeFields testMain() {\n"
       "    NativeFields obj = new NativeFields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Zone zone;
     HandleScope scope;
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
     const int kNumNativeFields = 4;
 
     // Create a test library.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Create a native wrapper class with native fields.
     result = Dart_CreateNativeWrapperClass(
         lib,
         Dart_NewString("NativeFieldsWrapper"),
         kNumNativeFields);
 
     // Load up a test script in the test library.
 
     // Invoke a function which returns an object of type NativeFields.
     result = Dart_InvokeStatic(lib,
                                Dart_NewString("NativeFieldsTest"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(retobj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
     Instance& obj = Instance::Handle();
-    obj ^= Api::UnwrapHandle(retobj);
+    obj ^= Api::UnwrapHandle(result);
     const Class& cls = Class::Handle(obj.clazz());
     // We expect the newly created "NativeFields" object to have
     // 2 dart instance fields (fld1, fld2) and kNumNativeFields native fields.
     // Hence the size of an instance of "NativeFields" should be
     // (kNumNativeFields + 2) * kWordSize + sizeof the header word.
     // We check to make sure the instance size computed by the VM matches
     // our expectations.
     EXPECT_EQ(Utils::RoundUp(((kNumNativeFields + 2) * kWordSize) + kWordSize,
                              kObjectAlignment),
               cls.instance_size());
@@ skipping 12 matching lines @@
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class NativeFieldsTest {\n"
       "  static NativeFields testMain() {\n"
       "    NativeFields obj = new NativeFields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object of type NativeFields.
     result = Dart_InvokeStatic(lib,
                                Dart_NewString("NativeFieldsTest"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
     // We expect this to fail as class "NativeFields" extends
     // "NativeFieldsWrapper" and there is no definition of it either
     // in the dart code or through the native field injection mechanism.
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(NativeFieldAccess) {
   const char* kScriptChars =
       "class NativeFields extends NativeFieldsWrapper {\n"
       "  NativeFields(int i, int j) : fld1 = i, fld2 = j {}\n"
       "  int fld1;\n"
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class NativeFieldsTest {\n"
       "  static NativeFields testMain() {\n"
       "    NativeFields obj = new NativeFields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
     const int kNumNativeFields = 4;
 
     // Create a test library.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Create a native wrapper class with native fields.
     result = Dart_CreateNativeWrapperClass(
         lib,
         Dart_NewString("NativeFieldsWrapper"),
         kNumNativeFields);
 
     // Load up a test script in it.
 
     // Invoke a function which returns an object of type NativeFields.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("NativeFieldsTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("NativeFieldsTest"),
+                                           Dart_NewString("testMain"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     // Now access and set various instance fields of the returned object.
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld3"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(10, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(10, value);
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(20, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(20, value);
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("fld2"),
                                    Dart_NewInteger(40));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetInstanceField(retobj,
                                    Dart_NewString("fld1"),
                                    Dart_NewInteger(40));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(40, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(40, value);
 
     // Now access and set various native instance fields of the returned object.
     const int kNativeFld0 = 0;
     const int kNativeFld1 = 1;
     const int kNativeFld2 = 2;
     const int kNativeFld3 = 3;
     const int kNativeFld4 = 4;
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld4);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld0);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT_EQ(0, Dart_GetResultAsCIntptr(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld1);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT_EQ(0, Dart_GetResultAsCIntptr(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld2);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT_EQ(0, Dart_GetResultAsCIntptr(result));
+    intptr_t field_value = 0;
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld4, &field_value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld0, &field_value);
+    EXPECT(Dart_IsValid(result));
+    EXPECT_EQ(0, field_value);
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld1, &field_value);
+    EXPECT(Dart_IsValid(result));
+    EXPECT_EQ(0, field_value);
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld2, &field_value);
+    EXPECT(Dart_IsValid(result));
+    EXPECT_EQ(0, field_value);
     result = Dart_SetNativeInstanceField(retobj, kNativeFld4, 40);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld0, 4);
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld1, 40);
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld2, 400);
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld3, 4000);
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld3);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT_EQ(4000, Dart_GetResultAsCIntptr(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld3, &field_value);
+    EXPECT(Dart_IsValid(result));
+    EXPECT_EQ(4000, field_value);
 
     // Now re-access various dart instance fields of the returned object
     // to ensure that there was no corruption while setting native fields.
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(40, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(40, value);
     result = Dart_GetInstanceField(retobj, Dart_NewString("fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(20, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(20, value);
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(NegativeNativeFieldAccess) {
   const char* kScriptChars =
       "class NativeFields {\n"
       "  NativeFields(int i, int j) : fld1 = i, fld2 = j {}\n"
       "  int fld1;\n"
       "  final int fld2;\n"
       "  static int fld3;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class NativeFieldsTest {\n"
       "  static NativeFields testMain1() {\n"
       "    NativeFields obj = new NativeFields(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "  static Function testMain2() {\n"
       "    return function() {};\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Zone zone;
     HandleScope scope;
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object of type NativeFields.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("NativeFieldsTest"),
-                               Dart_NewString("testMain1"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("NativeFieldsTest"),
+                                           Dart_NewString("testMain1"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
-
     // Now access and set various native instance fields of the returned object.
     // All of these tests are expected to return failure as there are no
     // native fields in an instance of NativeFields.
     const int kNativeFld0 = 0;
     const int kNativeFld1 = 1;
     const int kNativeFld2 = 2;
     const int kNativeFld3 = 3;
     const int kNativeFld4 = 4;
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld4);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld0);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld1);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld2);
-    EXPECT(!Dart_IsValidResult(result));
+    intptr_t value = 0;
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld4, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld0, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld1, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld2, &value);
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld4, 40);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld3, 40);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld0, 400);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     // Invoke a function which returns a closure object.
-    result = Dart_InvokeStatic(lib,
+    retobj = Dart_InvokeStatic(lib,
                                Dart_NewString("NativeFieldsTest"),
                                Dart_NewString("testMain2"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    retobj = Dart_GetResult(result);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld4);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld0);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld1);
-    EXPECT(!Dart_IsValidResult(result));
-    result = Dart_GetNativeInstanceField(retobj, kNativeFld2);
-    EXPECT(!Dart_IsValidResult(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld4, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld0, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld1, &value);
+    EXPECT(!Dart_IsValid(result));
+    result = Dart_GetNativeInstanceField(retobj, kNativeFld2, &value);
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld4, 40);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld3, 40);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     result = Dart_SetNativeInstanceField(retobj, kNativeFld0, 400);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(GetStaticField_RunsInitializer) {
   const char* kScriptChars =
       "class TestClass  {\n"
       "  static final int fld1 = 7;\n"
       "  static int fld2 = 11;\n"
       "  static void testMain() {\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object.
     result = Dart_InvokeStatic(lib,
                                Dart_NewString("TestClass"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
 
-    result = Dart_GetClass(lib, Dart_NewString("TestClass"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle cls = Dart_GetResult(result);
+    Dart_Handle cls = Dart_GetClass(lib, Dart_NewString("TestClass"));
+    EXPECT(Dart_IsValid(cls));
 
     // For uninitialized fields, the getter is returned
     result = Dart_GetStaticField(cls, Dart_NewString("fld1"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(7, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(7, value);
 
     result = Dart_GetStaticField(cls, Dart_NewString("fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(11, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(11, value);
 
     // Overwrite fld2
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("fld2"),
                                  Dart_NewInteger(13));
-    EXPECT(Dart_IsValidResult(result));
+    EXPECT(Dart_IsValid(result));
 
     // We now get the new value for fld2, not the initializer
     result = Dart_GetStaticField(cls, Dart_NewString("fld2"));
-    EXPECT(Dart_IsValidResult(result));
-    result = Dart_IntegerValue(Dart_GetResult(result));
-    EXPECT_EQ(13, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(13, value);
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(StaticFieldNotFound) {
   const char* kScriptChars =
       "class TestClass  {\n"
       "  static void testMain() {\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function.
     result = Dart_InvokeStatic(lib,
                                Dart_NewString("TestClass"),
                                Dart_NewString("testMain"),
                                0,
                                NULL);
 
-    result = Dart_GetClass(lib, Dart_NewString("TestClass"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle cls = Dart_GetResult(result);
+    Dart_Handle cls = Dart_GetClass(lib, Dart_NewString("TestClass"));
+    EXPECT(Dart_IsValid(cls));
 
     result = Dart_GetStaticField(cls, Dart_NewString("not_found"));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     EXPECT_STREQ("Specified field is not found in the class",
-                 Dart_GetErrorCString(result));
+                 Dart_GetError(result));
 
     result = Dart_SetStaticField(cls,
                                  Dart_NewString("not_found"),
                                  Dart_NewInteger(13));
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
     EXPECT_STREQ("Specified field is not found in the class",
-                 Dart_GetErrorCString(result));
+                 Dart_GetError(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(InvokeDynamic) {
   const char* kScriptChars =
       "class InvokeDynamic {\n"
       "  InvokeDynamic(int i, int j) : fld1 = i, fld2 = j {}\n"
       "  int method1(int i) { return i + fld1 + fld2 + fld4; }\n"
       "  static int method2(int i) { return i + fld4; }\n"
       "  int fld1;\n"
       "  final int fld2;\n"
       "  static final int fld4 = 10;\n"
       "}\n"
       "class InvokeDynamicTest {\n"
       "  static InvokeDynamic testMain() {\n"
       "    InvokeDynamic obj = new InvokeDynamic(10, 20);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Zone zone;
     HandleScope scope;
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object of type InvokeDynamic.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("InvokeDynamicTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("InvokeDynamicTest"),
+                                           Dart_NewString("testMain"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
 
     // Now invoke a dynamic method and check the result.
     Dart_Handle dart_arguments[1];
     dart_arguments[0] = Dart_NewInteger(1);
     result = Dart_InvokeDynamic(retobj,
                                 Dart_NewString("method1"),
                                 1,
                                 dart_arguments);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle obj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(obj));
-    EXPECT(Dart_IsInteger(obj));
-    result = Dart_IntegerValue(obj);
-    EXPECT_EQ(41, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(Dart_IsInteger(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(41, value);
 
     result = Dart_InvokeDynamic(retobj, Dart_NewString("method2"), 0, NULL);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     result = Dart_InvokeDynamic(retobj, Dart_NewString("method1"), 0, NULL);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(InvokeClosure) {
   const char* kScriptChars =
       "class InvokeClosure {\n"
@@ skipping 12 matching lines @@
       "}\n"
       "class InvokeClosureTest {\n"
       "  static Function testMain1() {\n"
       "    InvokeClosure obj = new InvokeClosure(10, 20);\n"
       "    return obj.method1(10);\n"
       "  }\n"
       "  static Function testMain2() {\n"
       "    return InvokeClosure.method2(10);\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Zone zone;
     HandleScope scope;
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns a closure.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("InvokeClosureTest"),
-                               Dart_NewString("testMain1"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("InvokeClosureTest"),
+                                           Dart_NewString("testMain1"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     EXPECT(Dart_IsClosure(retobj));
     EXPECT(!Dart_IsClosure(Dart_NewInteger(101)));
 
     // Now invoke the closure and check the result.
     Dart_Handle dart_arguments[1];
     dart_arguments[0] = Dart_NewInteger(1);
     result = Dart_InvokeClosure(retobj, 1, dart_arguments);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle obj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(obj));
-    EXPECT(Dart_IsInteger(obj));
-    result = Dart_IntegerValue(obj);
-    EXPECT_EQ(51, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(Dart_IsInteger(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(51, value);
 
     // Invoke closure with wrong number of args, should result in exception.
     result = Dart_InvokeClosure(retobj, 0, NULL);
-    EXPECT(Dart_IsValidResult(result));
-    obj = Dart_GetResult(result);
-    EXPECT(Dart_ExceptionOccurred(obj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(Dart_ExceptionOccurred(result));
 
     // Invoke a function which returns a closure.
-    result = Dart_InvokeStatic(lib,
+    retobj = Dart_InvokeStatic(lib,
                                Dart_NewString("InvokeClosureTest"),
                                Dart_NewString("testMain2"),
                                0,
                                NULL);
-    EXPECT(Dart_IsValidResult(result));
-    retobj = Dart_GetResult(result);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     EXPECT(Dart_IsClosure(retobj));
     EXPECT(!Dart_IsClosure(Dart_NewString("abcdef")));
 
     // Now invoke the closure and check the result (should be an exception).
     dart_arguments[0] = Dart_NewInteger(1);
     result = Dart_InvokeClosure(retobj, 1, dart_arguments);
-    retobj = Dart_GetResult(result);
-    EXPECT(Dart_ExceptionOccurred(retobj));
+    EXPECT(Dart_ExceptionOccurred(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 void ExceptionNative(Dart_NativeArguments args) {
   Dart_Handle param = Dart_GetNativeArgument(args, 0);
   Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
@@ skipping 18 matching lines @@
       "     try { method1(10); } catch(var a) { return 5; } return 10;\n"
       "  }\n"
       "  int fld1;\n"
       "}\n"
       "class ThrowExceptionTest {\n"
       "  static ThrowException testMain() {\n"
       "    ThrowException obj = new ThrowException(10);\n"
       "    return obj;\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   Isolate* isolate = Isolate::Current();
   EXPECT(isolate != NULL);
   ApiState* state = isolate->api_state();
   EXPECT(state != NULL);
   {
     intptr_t size = state->ZoneSizeInBytes();
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Load up a test script which extends the native wrapper class.
     Dart_Handle lib = TestCase::LoadTestScript(
         kScriptChars,
         reinterpret_cast<Dart_NativeEntryResolver>(native_lookup));
 
     // Invoke a function which returns an object of type ThrowException.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("ThrowExceptionTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
+    Dart_Handle retobj = Dart_InvokeStatic(lib,
+                                           Dart_NewString("ThrowExceptionTest"),
+                                           Dart_NewString("testMain"),
+                                           0,
+                                           NULL);
+    EXPECT(Dart_IsValid(retobj));
     EXPECT(!Dart_ExceptionOccurred(retobj));
 
     // Throwing an exception here should result in an error.
     result = Dart_ThrowException(retobj);
-    EXPECT(!Dart_IsValidResult(result));
+    EXPECT(!Dart_IsValid(result));
 
     // Now invoke method2 which invokes a natve method where it is
     // ok to throw an exception, check the result which would indicate
     // if an exception was thrown or not.
     result = Dart_InvokeDynamic(retobj, Dart_NewString("method2"), 0, NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle obj = Dart_GetResult(result);
-    EXPECT(!Dart_ExceptionOccurred(obj));
-    EXPECT(Dart_IsInteger(obj));
-    result = Dart_IntegerValue(obj);
-    EXPECT_EQ(5, Dart_GetResultAsCInt64(result));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!Dart_ExceptionOccurred(result));
+    EXPECT(Dart_IsInteger(result));
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT_EQ(5, value);
 
     Dart_ExitScope();  // Exit the Dart API scope.
     EXPECT_EQ(size, state->ZoneSizeInBytes());
   }
   Dart_ShutdownIsolate();
 }
 
 
 void NativeArgumentCounter(Dart_NativeArguments args) {
   Dart_EnterScope();
@@ skipping 20 matching lines @@
       "  }"
       "}";
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();
     Dart_Handle lib = TestCase::LoadTestScript(
         kScriptChars,
         reinterpret_cast<Dart_NativeEntryResolver>(gnac_lookup));
 
-    Dart_Result result = Dart_InvokeStatic(lib,
+    Dart_Handle result = Dart_InvokeStatic(lib,
                                            Dart_NewString("Test"),
                                            Dart_NewString("testMain"),
                                            0,
                                            NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle result_obj = Dart_GetResult(result);
-    EXPECT(Dart_IsInteger(result_obj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(Dart_IsInteger(result));
 
-    result = Dart_IntegerValue(result_obj);
-    EXPECT(Dart_IsValidResult(result));
-    int64_t value = Dart_GetResultAsCInt64(result);
+    int64_t value = 0;
+    result = Dart_IntegerValue(result, &value);
+    EXPECT(Dart_IsValid(result));
     EXPECT_EQ(3, value);
 
     Dart_ExitScope();
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(InstanceOf) {
   const char* kScriptChars =
       "class OtherClass {\n"
       "  static returnNull() { return null; }\n"
       "}\n"
       "class InstanceOfTest {\n"
       "  InstanceOfTest() {}\n"
       "  static InstanceOfTest testMain() {\n"
       "    return new InstanceOfTest();\n"
       "  }\n"
       "}\n";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
     // Invoke a function which returns an object of type InstanceOf..
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("InstanceOfTest"),
-                               Dart_NewString("testMain"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle instanceOfTestObj = Dart_GetResult(result);
+    Dart_Handle instanceOfTestObj =
+        Dart_InvokeStatic(lib,
+                          Dart_NewString("InstanceOfTest"),
+                          Dart_NewString("testMain"),
+                          0,
+                          NULL);
+    EXPECT(Dart_IsValid(instanceOfTestObj));
     EXPECT(!Dart_ExceptionOccurred(instanceOfTestObj));
 
     // Fetch InstanceOfTest class.
-    result = Dart_GetClass(lib, Dart_NewString("InstanceOfTest"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle cls = Dart_GetResult(result);
+    Dart_Handle cls = Dart_GetClass(lib, Dart_NewString("InstanceOfTest"));
+    EXPECT(Dart_IsValid(cls));
     EXPECT(!Dart_ExceptionOccurred(cls));
 
     // Now check instanceOfTestObj reported as an instance of
     // InstanceOfTest class.
-    result = Dart_IsInstanceOf(instanceOfTestObj, cls);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(Dart_GetResultAsCBoolean(result));
+    bool is_instance = false;
+    result = Dart_IsInstanceOf(instanceOfTestObj, cls, &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(is_instance);
 
     // Fetch OtherClass and check if instanceOfTestObj is instance of it.
-    result = Dart_GetClass(lib, Dart_NewString("OtherClass"));
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle otherClass = Dart_GetResult(result);
+    Dart_Handle otherClass = Dart_GetClass(lib, Dart_NewString("OtherClass"));
+    EXPECT(Dart_IsValid(otherClass));
     EXPECT(!Dart_ExceptionOccurred(otherClass));
 
-    result = Dart_IsInstanceOf(instanceOfTestObj, otherClass);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(!Dart_GetResultAsCBoolean(result));
+    result = Dart_IsInstanceOf(instanceOfTestObj, otherClass, &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!is_instance);
 
     // Check that primitives are not instances of InstanceOfTest class.
-    result = Dart_IsInstanceOf(Dart_NewString("a string"), otherClass);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(!Dart_GetResultAsCBoolean(result));
+    result = Dart_IsInstanceOf(Dart_NewString("a string"), otherClass,
+                               &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!is_instance);
 
-    result = Dart_IsInstanceOf(Dart_NewInteger(42), otherClass);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(!Dart_GetResultAsCBoolean(result));
+    result = Dart_IsInstanceOf(Dart_NewInteger(42), otherClass, &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!is_instance);
 
-    result = Dart_IsInstanceOf(Dart_NewBoolean(true), otherClass);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(!Dart_GetResultAsCBoolean(result));
+    result = Dart_IsInstanceOf(Dart_NewBoolean(true), otherClass, &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!is_instance);
 
     // Check that null is not an instance of InstanceOfTest class.
-    result = Dart_InvokeStatic(lib,
-                               Dart_NewString("OtherClass"),
-                               Dart_NewString("returnNull"),
-                               0,
-                               NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle null = Dart_GetResult(result);
+    Dart_Handle null = Dart_InvokeStatic(lib,
+                                         Dart_NewString("OtherClass"),
+                                         Dart_NewString("returnNull"),
+                                         0,
+                                         NULL);
+    EXPECT(Dart_IsValid(null));
     EXPECT(!Dart_ExceptionOccurred(null));
 
-    result = Dart_IsInstanceOf(null, otherClass);
-    EXPECT(Dart_IsValidResult(result));
-    EXPECT(!Dart_GetResultAsCBoolean(result));
+    result = Dart_IsInstanceOf(null, otherClass, &is_instance);
+    EXPECT(Dart_IsValid(result));
+    EXPECT(!is_instance);
 
     // Check that error is returned if null is passed as a class argument.
-    result = Dart_IsInstanceOf(null, null);
-    EXPECT(!Dart_IsValidResult(result));
+    result = Dart_IsInstanceOf(null, null, &is_instance);
+    EXPECT(!Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(NullReceiver) {
   Dart_CreateIsolate(NULL, NULL);
   Dart_EnterScope();  // Enter a Dart API scope for the unit test.
   {
     Zone zone;
     HandleScope hs;
 
     Dart_Handle function_name = Dart_NewString("toString");
     const int number_of_arguments = 0;
     Dart_Handle null_receiver = Api::NewLocalHandle(Object::Handle());
-    Dart_Result result = Dart_InvokeDynamic(null_receiver,
+    Dart_Handle result = Dart_InvokeDynamic(null_receiver,
                                             function_name,
                                             number_of_arguments,
                                             NULL);
-    EXPECT(Dart_IsValidResult(result));
-    Dart_Handle retobj = Dart_GetResult(result);
-    EXPECT(Dart_IsString(retobj));
+    EXPECT(Dart_IsValid(result));
+    EXPECT(Dart_IsString(result));
 
     // Should throw a NullPointerException. Disabled due to bug 5415268.
     /*
     Dart_Handle function_name2 = Dart_NewString("NoNoNo");
     result = Dart_InvokeDynamic(null_receiver,
                                 function_name2,
                                 number_of_arguments,
                                 dart_arguments);
-    EXPECT(Dart_IsValidResult(result));
-    retobj = Dart_GetResult(result);
-    EXPECT(Dart_ExceptionOccurred(retobj)); */
+    EXPECT(Dart_IsValid(result));
+    EXPECT(Dart_ExceptionOccurred(result)); */
   }
   Dart_ExitScope();  // Exit the Dart API scope.
   Dart_ShutdownIsolate();
 }
 
 
-static Dart_Result library_handler(Dart_LibraryTag tag,
+static Dart_Handle library_handler(Dart_LibraryTag tag,
                                    Dart_Handle library,
                                    Dart_Handle url) {
   if (tag == kCanonicalizeUrl) {
-    return Dart_ResultAsObject(url);
+    return url;
   }
-  return Dart_ResultAsObject(Dart_NewBoolean(true));
+  return Api::Success();
 }
 
 
 UNIT_TEST_CASE(ImportLibrary1) {
   const char* kScriptChars =
       "#import('library1.dart');"
       "#import('library2.dart');"
       "var foo;  // library2 defines foo, so should be error."
       "main() {}";
   const char* kLibrary1Chars =
       "#library('library1.dart');"
       "#import('library2.dart');"
       "var foo1;";
   const char* kLibrary2Chars =
       "#library('library2.dart');"
       "var foo;";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle url = Dart_NewString(TestCase::url());
     Dart_Handle source = Dart_NewString(kScriptChars);
     result = Dart_LoadScript(url, source, library_handler);
 
     url = Dart_NewString("library1.dart");
     source = Dart_NewString(kLibrary1Chars);
     Dart_LoadLibrary(url, source);
 
     url = Dart_NewString("library2.dart");
     source = Dart_NewString(kLibrary2Chars);
     Dart_LoadLibrary(url, source);
 
-    result = Dart_InvokeStatic(Dart_GetResult(result),
+    result = Dart_InvokeStatic(result,
                                Dart_NewString(""),
                                Dart_NewString("main"),
                                0,
                                NULL);
-    assert(!Dart_IsValidResult(result));
+    assert(!Dart_IsValid(result));
     EXPECT_STREQ("Duplicate definition : 'foo' is defined in"
                  " 'library2.dart' and 'dart:test-lib'\n",
-                 Dart_GetErrorCString(result));
+                 Dart_GetError(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(ImportLibrary2) {
   const char* kScriptChars =
       "#import('library1.dart');"
       "var foo;"
       "main() {}";
   const char* kLibrary1Chars =
       "#library('library1.dart');"
       "#import('library2.dart');"
       "var foo1;";
   const char* kLibrary2Chars =
       "#library('library2.dart');"
       "#import('library1.dart');"
       "var foo;";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle url = Dart_NewString(TestCase::url());
     Dart_Handle source = Dart_NewString(kScriptChars);
     result = Dart_LoadScript(url, source, library_handler);
 
     url = Dart_NewString("library1.dart");
     source = Dart_NewString(kLibrary1Chars);
     Dart_LoadLibrary(url, source);
 
     url = Dart_NewString("library2.dart");
     source = Dart_NewString(kLibrary2Chars);
     Dart_LoadLibrary(url, source);
 
-    result = Dart_InvokeStatic(Dart_GetResult(result),
+    result = Dart_InvokeStatic(result,
                                Dart_NewString(""),
                                Dart_NewString("main"),
                                0,
                                NULL);
-    assert(Dart_IsValidResult(result));
+    assert(Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(ImportLibrary3) {
   const char* kScriptChars =
       "#import('library2.dart');"
       "#import('library1.dart');"
       "var foo_top = 10;  // foo has dup def. So should be an error."
       "main() {}";
   const char* kLibrary1Chars =
       "#library('library1.dart');"
       "var foo;";
   const char* kLibrary2Chars =
       "#library('library2.dart');"
       "var foo;";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle url = Dart_NewString(TestCase::url());
     Dart_Handle source = Dart_NewString(kScriptChars);
     result = Dart_LoadScript(url, source, library_handler);
 
     url = Dart_NewString("library2.dart");
     source = Dart_NewString(kLibrary2Chars);
     Dart_LoadLibrary(url, source);
 
     url = Dart_NewString("library1.dart");
     source = Dart_NewString(kLibrary1Chars);
     Dart_LoadLibrary(url, source);
 
-    result = Dart_InvokeStatic(Dart_GetResult(result),
+    result = Dart_InvokeStatic(result,
                                Dart_NewString(""),
                                Dart_NewString("main"),
                                0,
                                NULL);
-    assert(!Dart_IsValidResult(result));
+    assert(!Dart_IsValid(result));
     EXPECT_STREQ("Duplicate definition : 'foo' is defined in"
                  " 'library1.dart' and 'library2.dart'\n",
-                 Dart_GetErrorCString(result));
+                 Dart_GetError(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(ImportLibrary4) {
   const char* kScriptChars =
       "#import('libraryA.dart');"
@@ skipping 18 matching lines @@
       "#import('libraryF.dart');"
       "var fooD;";
   const char* kLibraryEChars =
       "#library('libraryE.dart');"
       "#import('libraryC.dart');"
       "#import('libraryF.dart');"
       "var fooE = 10;  //fooC has duplicate def. so should be an error.";
   const char* kLibraryFChars =
       "#library('libraryF.dart');"
       "var fooC;";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle url = Dart_NewString(TestCase::url());
     Dart_Handle source = Dart_NewString(kScriptChars);
     result = Dart_LoadScript(url, source, library_handler);
 
@@ skipping 14 matching lines @@
     Dart_LoadLibrary(url, source);
 
     url = Dart_NewString("libraryF.dart");
     source = Dart_NewString(kLibraryFChars);
     Dart_LoadLibrary(url, source);
 
     url = Dart_NewString("libraryE.dart");
     source = Dart_NewString(kLibraryEChars);
     Dart_LoadLibrary(url, source);
 
-    result = Dart_InvokeStatic(Dart_GetResult(result),
+    result = Dart_InvokeStatic(result,
                                Dart_NewString(""),
                                Dart_NewString("main"),
                                0,
                                NULL);
-    assert(!Dart_IsValidResult(result));
+    assert(!Dart_IsValid(result));
     EXPECT_STREQ("Duplicate definition : 'fooC' is defined in"
                  " 'libraryF.dart' and 'libraryC.dart'\n",
-                 Dart_GetErrorCString(result));
+                 Dart_GetError(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 
 
 UNIT_TEST_CASE(ImportLibrary5) {
   const char* kScriptChars =
       "#import('lib.dart');"
       "interface Y {"
       "  void set handler(void callback(List<int> x));"
       "}"
       "void main() {}";
   const char* kLibraryChars =
       "#library('lib.dart');"
       "interface X {"
       "  void set handler(void callback(List<int> x));"
       "}";
-  Dart_Result result;
+  Dart_Handle result;
 
   Dart_CreateIsolate(NULL, NULL);
   {
     Dart_EnterScope();  // Start a Dart API scope for invoking API functions.
 
     // Create a test library and Load up a test script in it.
     Dart_Handle url = Dart_NewString(TestCase::url());
     Dart_Handle source = Dart_NewString(kScriptChars);
     result = Dart_LoadScript(url, source, library_handler);
 
     url = Dart_NewString("lib.dart");
     source = Dart_NewString(kLibraryChars);
     Dart_LoadLibrary(url, source);
 
-    result = Dart_InvokeStatic(Dart_GetResult(result),
+    result = Dart_InvokeStatic(result,
                                Dart_NewString(""),
                                Dart_NewString("main"),
                                0,
                                NULL);
-    assert(Dart_IsValidResult(result));
+    assert(Dart_IsValid(result));
 
     Dart_ExitScope();  // Exit the Dart API scope.
   }
   Dart_ShutdownIsolate();
 }
 #endif  // TARGET_ARCH_IA32.
 
 }  // namespace dart