Struct ComonadCtx 

pub struct ComonadCtx<E, A> { /* private fields */ }

A comonad-style context: wraps a focused value with an environment.

Models (env, focus) pairs where focus is the current value and env captures additional context (e.g., for zipper traversal).

Implementations

impl<E: Clone, A: Clone> ComonadCtx<E, A>

pub fn new(env: E, focus: A) -> Self

Create a new comonad context.

pub fn extract(&self) -> A

Extract the focused value (comonad extract).

pub fn duplicate(&self) -> ComonadCtx<E, ComonadCtx<E, A>>

Duplicate: produce a context focused on itself.

pub fn extend<B, F: Fn(&ComonadCtx<E, A>) -> B>(&self, f: F) -> ComonadCtx<E, B>

Extend: apply a function to the whole context, producing a new context.

pub fn map<B, F: FnOnce(A) -> B>(self, f: F) -> ComonadCtx<E, B>

Map over the focused value.

pub fn env(&self) -> &E

Get a reference to the environment.

Trait Implementations

impl<E: Clone, A: Clone> Clone for ComonadCtx<E, A>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.