Enum OpenTree

pub enum OpenTree<Ty, Op> {
    Id(Ty),
    Comp(Tree<Option<Op>>),
}

An open tree, or tree with boundary.

In a non-empty open tree, backed by a [Tree], each node carries either an operation or a null value. The null nodes constitute the boundary of the tree. It is an error for null nodes to have children or for the root to be null. Failure to maintain this invariant may result in panics.

Compare with the Path data type, of which this type may be considered a generalization.

Variants

Id(Ty)

The identity, or empty, tree on a type.

Comp(Tree<Option<Op>>)

A rooted tree, representing a nonempty composite of operations.

Implementations

impl<Ty, Op> OpenTree<Ty, Op>

pub fn empty(ty: Ty) -> Self

Constructs the empty or identity tree.

pub fn single(op: Op, arity: usize) -> Self

Constructs a singleton tree with the given arity.

pub fn graft(subtrees: impl IntoIterator<Item = Self>, op: Op) -> Self

Constructs an open tree by grafting subtrees onto a root operation.

The root operation is assumed to have arity equal to the number of subtrees.

pub fn linear(iter: impl IntoIterator<Item = Op>) -> Option<Self>

Constructs a linear open tree from a sequence of unary operations.

Each operation is assumed to be unary. This constructor returns nothing if the sequence is empty.

pub fn arity(&self) -> usize

Gets the arity of the open tree.

The arity of an open tree is the number of boundary nodes in it.

pub fn size(&self) -> usize

Gets the size of the open tree.

The size of an open tree is the number of non-boundary nodes in it, ignoring orphans.

pub fn is_empty(&self) -> bool

Is the open tree empty?

pub fn only(self) -> Option<Op>

Extracts the unique node in a tree of size 1.

This method is a one-sided inverse to OpenTree::single.

pub fn is_isomorphic_to(&self, other: &Self) -> bool

where Ty: Eq, Op: Eq,

Is the open tree isomorphic to another?

Open trees should generally be compared for isomorphism rather than equality because, among other reasons, the flatten method produces orphan nodes.

pub fn map<CodOp>(self, f: impl FnMut(Op) -> CodOp) -> OpenTree<Ty, CodOp>

Maps over the operations in the tree.

impl<Ty, Op> OpenTree<Ty, OpenTree<Ty, Op>>

pub fn flatten(self) -> OpenTree<Ty, Op>

Flattens an open tree of open trees into a single open tree.

Trait Implementations

impl<Ty: Clone, Op: Clone> Clone for OpenTree<Ty, Op>

fn clone(&self) -> OpenTree<Ty, Op>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<Ty: Debug, Op: Debug> Debug for OpenTree<Ty, Op>

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

Formats the value using the given formatter.

impl<E, ProE, Sq> From<OpenTree<ProE, DblNode<E, Sq>>> for DblTree<E, ProE, Sq>

fn from(value: OpenTree<ProE, DblNode<E, Sq>>) -> Self

Converts to this type from the input type.

impl<Ty, Op> From<Tree<Option<Op>>> for OpenTree<Ty, Op>

fn from(value: Tree<Option<Op>>) -> Self

Converts to this type from the input type.

impl<Ty: PartialEq, Op: PartialEq> PartialEq for OpenTree<Ty, Op>

fn eq(&self, other: &OpenTree<Ty, Op>) -> 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<Ty: Eq, Op: Eq> Eq for OpenTree<Ty, Op>

impl<Ty, Op> StructuralPartialEq for OpenTree<Ty, Op>