Although the %Close method doesn't do anything, there is a useful %OnClose callback, where you can do some cleanup if needed, such killing a temporary global.

I've had the privilege of working with John at George James. Besides being just a nice bloke, he's a genius.

> messages seems not to purge correctly

That might be if you use:

Property Text as %Stream.GlobalCharacter (or other global based streams)

And then in code: Set Object.Text=PointerToAnotherStream

The original Global node for the property stream gets 'orphaned', it is not referenced by any object and won't be purged (or garbage collected) if the object is deleted or gets out of scope.

The correct way is to use Do Object.Property.CopyFrom(PointerToAnotherStream)