Warnings for new C++ buffer API

src/node_buffer.h

@@ -4,6 +4,7 @@
 #include <node.h>
 #include <node_object_wrap.h>
 #include <v8.h>
+#include <assert.h>
 
 namespace node {
 
@@ -39,8 +40,16 @@ class Buffer : public ObjectWrap {
   static char* Data(v8::Handle<v8::Object>);
   static size_t Length(v8::Handle<v8::Object>);
 
-  char* data();
-  size_t length() const { return length_; }
+  char* data() {
+    assert(0 && "v0.3 API change: Use node::Buffer::Data().");
+    return NULL;
+  }
+
+
+  size_t length() const {
+    assert(0 && "v0.3 API change: Use node::Buffer::Length().");
+    return 0;
+  }
 
   int AsciiWrite(char *string, int offset, int length);
   int Utf8Write(char *string, int offset, int length);