Struct Hierarchy 

pub struct Hierarchy { /* private fields */ }

Hierarchical structure on top of a PortGraph.

The order of child nodes is maintained as a doubly linked list which supports efficient insertion and removal at any point in the list.

Implementations

impl Hierarchy

pub const fn new() -> Self

Creates a new empty layout.

pub fn with_capacity(capacity: usize) -> Self

Creates a new empty layout with the given capacity.

impl Hierarchy

pub fn push_child( &mut self, node: NodeIndex, parent: NodeIndex, ) -> Result<(), AttachError>

Attaches a node as the last child of a parent node.

Errors

• When the attachment would introduce a cycle.
• When the node is already attached.

Panics

Panics when the parent node will have more than u32::MAX children.

pub fn push_front_child( &mut self, node: NodeIndex, parent: NodeIndex, ) -> Result<(), AttachError>

Attaches a node as the first child of a parent node.

Errors

• When the attachment would introduce a cycle.
• When the node is already attached.

Panics

Panics when the parent node will have more than u32::MAX children.

pub fn insert_before( &mut self, node: NodeIndex, before: NodeIndex, ) -> Result<(), AttachError>

Attaches a node before another node within the other node’s parent.

Errors

• When the attachment would introduce a cycle.
• When the node is already attached.
• When the other node is a root.

Panics

Panics when the parent node will have more than u32::MAX children.

pub fn insert_after( &mut self, node: NodeIndex, after: NodeIndex, ) -> Result<(), AttachError>

Attaches a node after another node within the other node’s parent.

Errors

• When the attachment would introduce a cycle.
• When the node is already attached.
• When the other node is a root.

Panics

Panics when the parent node will have more than u32::MAX children.

pub fn detach(&mut self, node: NodeIndex) -> Option<NodeIndex>

Detaches a node from its parent, returning the former parent.

Does nothing and returns None when the node is a root.

pub fn detach_children(&mut self, node: NodeIndex)

Detaches all children from a node.

pub fn remove(&mut self, node: NodeIndex)

Removes a node from the hierarchy, detaching it from its parent and detaching all its children.

pub fn parent(&self, node: NodeIndex) -> Option<NodeIndex>

Returns a node’s parent or None if it is a root.

pub fn is_root(&self, node: NodeIndex) -> bool

Returns whether a node is a root.

pub fn first(&self, parent: NodeIndex) -> Option<NodeIndex>

Returns a node’s first child, if any.

pub fn last(&self, parent: NodeIndex) -> Option<NodeIndex>

Returns a node’s last child, if any.

pub fn next(&self, node: NodeIndex) -> Option<NodeIndex>

Returns the next sibling in the node’s parent, if any.

Also returns None if the node is a root.

pub fn prev(&self, node: NodeIndex) -> Option<NodeIndex>

Returns the previous sibling in the node’s parent, if any.

Also returns None if the node is a root.

pub fn children(&self, node: NodeIndex) -> Children<'_>

Iterates over the node’s children.

pub fn descendants(&self, node: NodeIndex) -> Descendants<'_>

Iterates over the node’s descendants.

Traverses the hierarchy in breadth-first order.

The iterator will yield the node itself first, followed by its children.

pub fn child_count(&self, node: NodeIndex) -> usize

Returns the number of the node’s children.

pub fn has_children(&self, node: NodeIndex) -> bool

Returns whether a node has any children.

pub fn swap_nodes(&mut self, a: NodeIndex, b: NodeIndex)

Swap the positions of two nodes.

pub fn rekey(&mut self, old: NodeIndex, new: NodeIndex)

Changes the index of a node from old to new.

Panics

Panics if the index new is not a root without any children.

pub fn ensure_capacity(&mut self, capacity: usize)

Reserves enough capacity to fit a maximum node index without reallocating. Does nothing if there already is enough capacity.

pub fn shrink_to(&mut self, capacity: usize)

Reduces the capacity of the structure to capacity. Nodes with index higher than capacity are disconnected.

Does nothing when the capacity of the secondary map is already lower.

Trait Implementations

impl Clone for Hierarchy

fn clone(&self) -> Hierarchy

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Hierarchy

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

Formats the value using the given formatter.

impl Default for Hierarchy

fn default() -> Self

Returns the “default value” for a type.

impl<'a> From<&'a Hierarchy> for Cow<'a, Hierarchy>

fn from(hierarchy: &'a Hierarchy) -> Self

Converts to this type from the input type.

impl From<Hierarchy> for Cow<'_, Hierarchy>

fn from(hierarchy: Hierarchy) -> Self

Converts to this type from the input type.

impl PartialEq for Hierarchy

fn eq(&self, other: &Hierarchy) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Hierarchy