Struct Stacked 

pub struct Stacked<T> { /* private fields */ }

A helper type to implement the Stack trait

This type is a wrapper for any clonable type T that implements Stack on top of it. Access to the current topmost frame is granted via Deref and DerefMut.

The stack structure is implemented as a vector where the current value of the inner object is pushed when Stack::push is called, and popped when Stack::pop_n is called. This means that types used with Stacked should be efficiently clonable. Efficient clonability is often achieved in formally by using immutable/persistent data structures, usually from the rpds crate.

To construct a Stacked object, the underlying type must implement Default. The Stack traits suggests that popping out more frames than those pushed should result into an object equivalent to the Default instance. This requirement is satisfied by Stacked.

Implementations

impl<T: Default> Stacked<T>

pub fn new(current: T) -> Self

Creates a new default-valued stacked object.

pub fn into_current(self) -> T

Turns the stacked into the current topmost frame.

Trait Implementations

impl<T: Clone> Clone for Stacked<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Clone + Default> Default for Stacked<T>

fn default() -> Self

Returns the “default value” for a type.

impl<T: Clone + Default> Deref for Stacked<T>

type Target = T

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<T: Clone + Default> DerefMut for Stacked<T>

fn deref_mut(&mut self) -> &mut Self::Target

Mutably dereferences the value.

impl<T: Clone + Default> Stack for Stacked<T>

fn push(&mut self) -> Result<()>

Push the current state of the object to the stack.

fn pop_n(&mut self, n: usize) -> Result<()>

Pop n frames from the stack, restoring the state of the nth topmost frame.

fn pop(&mut self) -> Result<()>

Shortcut for pop_n(1)