Struct Tree 

pub struct Tree { /* private fields */ }

Arena-backed filesystem tree with stable 32-bit node indices.

Implementations

impl Tree

pub const fn new() -> Self

Create an empty tree.

pub fn add_root(&mut self, name: impl AsRef<Path>, data: EntryData) -> TreeIndex

Add a parentless node.

Panics

Panics if the tree exceeds its storage limits or allocation fails.

pub fn add_detached( &mut self, name: impl AsRef<Path>, data: EntryData, ) -> TreeIndex

Add a node that is not yet attached to the tree.

pub fn add_child( &mut self, parent: TreeIndex, name: impl AsRef<Path>, data: EntryData, ) -> TreeIndex

Add a child to parent, placing it before previously attached children.

Panics

Panics if parent is missing or the tree cannot grow.

pub fn try_add_root( &mut self, name: impl AsRef<Path>, data: EntryData, ) -> Result<TreeIndex, TreeError>

Try to add a parentless node.

pub fn try_add_child( &mut self, parent: TreeIndex, name: impl AsRef<Path>, data: EntryData, ) -> Result<TreeIndex, TreeError>

Try to add a child to parent.

pub fn attach( &mut self, parent: TreeIndex, child: TreeIndex, ) -> Result<(), TreeError>

Attach a parentless node to parent, before its existing children.

pub fn parent(&self, index: TreeIndex) -> Option<TreeIndex>

Return a node’s parent, or None for a parentless or missing node.

pub fn children(&self, index: TreeIndex) -> Children<'_>

Iterate a node’s children in reverse insertion order.

pub fn indices(&self) -> impl Iterator<Item = TreeIndex> + '_

Iterate all currently occupied node indices.

pub fn entry(&self, index: TreeIndex) -> Option<Entry<'_>>

Return an entry view for index.

pub fn data(&self, index: TreeIndex) -> Option<EntryData>

Return a copy of an entry’s metadata.

pub fn set_data(&mut self, index: TreeIndex, data: EntryData) -> bool

Replace an entry’s metadata, returning false if the index is missing.

pub fn update( &mut self, index: TreeIndex, edit: impl FnOnce(&mut EntryData), ) -> bool

Mutate an entry’s metadata, returning false if the index is missing.

pub fn name(&self, index: TreeIndex) -> Option<Cow<'_, Path>>

Return an entry’s arena-backed name.

pub fn rename( &mut self, index: TreeIndex, name: impl AsRef<Path>, ) -> Result<(), TreeError>

Replace an entry’s name. Old arena bytes remain reserved until the tree is dropped.

pub fn remove_subtree(&mut self, index: TreeIndex) -> usize

Remove index and all descendants, returning the number removed.

pub fn contains(&self, index: TreeIndex) -> bool

Return whether index refers to a live node.

pub fn len(&self) -> usize

Return the number of live nodes.

pub fn is_empty(&self) -> bool

Return whether this tree has no live nodes.

Trait Implementations

impl Clone for Tree

fn clone(&self) -> Tree

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Tree

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Tree

fn default() -> Self

Returns the “default value” for a type.