Struct StateMap 

pub struct StateMap { /* private fields */ }

A type-keyed registry holding at most one shared value per type — a minimal dependency-injection container.

Each value is keyed by its TypeId and stored behind an Arc, so reads hand out cheap shared handles. This backs AppBuilder::state and the State extractor; you rarely construct one directly.

use churust_core::StateMap;

let mut state = StateMap::new();
state.insert(42u32);
state.insert(String::from("hi"));
assert_eq!(*state.get::<u32>().unwrap(), 42);
assert_eq!(state.get::<String>().unwrap().as_str(), "hi");
assert!(state.get::<bool>().is_none());

Implementations

impl StateMap

pub fn new() -> Self

Create an empty registry. Equivalent to StateMap::default.

use churust_core::StateMap;
assert!(StateMap::new().get::<u32>().is_none());

pub fn insert<T: Send + Sync + 'static>(&mut self, value: T)

Insert (or replace) the single value held for type T.

use churust_core::StateMap;
let mut state = StateMap::new();
state.insert(1u8);
state.insert(2u8); // replaces the previous u8
assert_eq!(*state.get::<u8>().unwrap(), 2);

pub fn get<T: Send + Sync + 'static>(&self) -> Option<Arc<T>>

Get a shared Arc handle to the value for type T, or None if no value of that type has been inserted.

Trait Implementations

impl Clone for StateMap

fn clone(&self) -> StateMap

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for StateMap

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

Formats the value using the given formatter.

impl Default for StateMap

fn default() -> StateMap

Returns the “default value” for a type.