Operations on lazy tree contents.
val key : t -> contents_key option
force t forces evaluation of the lazy content value
t, or returns an error if no such value exists in the underlying repository.
force, but raises an exception if the lazy content value is not present in the underlying repository.
val clear : t -> unit
clear t clears
cache regulates the caching behaviour regarding the node's internal data which are be lazily loaded from the backend.
cache defaults to
true which may greatly reduce the IOs and the runtime but may also grealy increase the memory consumption.
cache = false doesn't replace a call to
clear, it only prevents the storing of new data, it doesn't discard the existing one.