However you make use of mixed revisions in your working copy, there are limitations to this flexibility.
First, you cannot commit the deletion of a file or directory that isn't fully up to date. If a newer version of the item exists in the repository, your attempt to delete will be rejected in order to prevent you from accidentally destroying changes you've not yet seen.
Second, you cannot commit a metadata change to a directory unless it's fully up to date. You'll learn about attaching “properties” to items in Chapter 3, Advanced Topics. A directory's working revision defines a specific set of entries and properties, and thus committing a property change to an out-of-date directory may destroy properties you've not yet seen.