tweak comments. fix copy to self case.
diff --git a/tinyxml2.cpp b/tinyxml2.cpp
index 0168d9b..5c459a6 100755
--- a/tinyxml2.cpp
+++ b/tinyxml2.cpp
@@ -2052,7 +2052,9 @@
 void XMLDocument::DeepCopy(XMLDocument* target)

 {

 	TIXMLASSERT(target);

-	TIXMLASSERT(target != this);

+    if (target == this) {

+        return; // technically success - a no-op.

+    }

 

 	target->Clear();

 	for (const XMLNode* node = this->FirstChild(); node; node = node->NextSibling()) {