Tree provides immutable, in-memory partial mirror of the store, with lazy reads and delayed writes.
Trees are like staging area in Git: they are immutable temporary non-persistent areas (they disappear if the host crash), held in memory for efficiency, where reads are done lazily and writes are done only when needed on commit: if you modify a key twice, only the last change will be written to the store when you commit.
val empty : treeempty is the empty tree. Empty trees do not have associated backend configuration values, as they can perform in-memory operation, independently of any given backend.
Note: there is another way to obtain an empty tree using `Node h where h is the hash of the empty tree for the current repository. Don't use (=) `Empty to check for tree tree emptiness, unless you really know what you are doing.
of_contents c is the subtree built from the contents c.
kind t k is the type of s in t. It could either be a tree node or some file contents. It is `Empty if k is not present in t.
list t key is the list of files and sub-nodes stored under k in t.
diff x y is the difference of contents between x and y.
find_all t k is Some (b, m) if k is associated to the contents b and metadata m in t and None if k is not present in t.
find is similar to find_all but it discards metadata.
Same as find_all but raise Invalid_arg if k is not present in t.
add t k c is the tree where the key k is bound to the contents c but is similar to t for other bindings.
remove t k is the tree where k bindings has been removed but is similar to t for other bindings.
find_tree t k is v if k is associated to v in t. It is `Empty if k is not present in t.
add_tree t k v is the tree where the key k is bound to the tree v but is similar to t for other bindings
The type for concrete trees.
to_concrete t is the concrete tree equivalent to the subtree t.