Add comment describing the interaction of WantsRawCommandString()/WantsCompletion() with the completion mechanism.


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@148521 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Interpreter/CommandObject.cpp b/source/Interpreter/CommandObject.cpp
index 63d93a2..7624e86 100644
--- a/source/Interpreter/CommandObject.cpp
+++ b/source/Interpreter/CommandObject.cpp
@@ -344,6 +344,10 @@
     StringList &matches
 )
 {
+    // Default implmentation of WantsCompletion() is !WantsRawCommandString().
+    // Subclasses who want raw command string but desire, for example,
+    // argument completion should override WantsCompletion() to return true,
+    // instead.
     if (WantsRawCommandString() && !WantsCompletion())
     {
         // FIXME: Abstract telling the completion to insert the completion character.