Struct State 

pub struct State<P, Q> { /* private fields */ }

State split into a public zone and per-player private zones, plus the match’s random generator.

Redaction is mechanical: a player’s observation is the public zone plus their own private entry, so there is no field to forget to strip. The backing map is not exposed; games reach private data through the accessors. Using this type is a convenience, not a requirement (Game::State is an associated type and can be any shape) but it makes the common hidden-info game turnkey.

The Prng lives here so it clones, serializes, and rewinds together with everything else: snapshot and resume are O(1), and a Reversible undo record can restore the stream position (see ARCHITECTURE.md). Games with their own State type should embed a Prng the same way.

Implementations

impl<P, Q> State<P, Q>

pub const fn new(public: P, seed: u64) -> Self

Creates a state with the given public zone, no private entries, and a generator seeded from seed.

pub const fn public(&self) -> &P

Returns the public zone, visible to everyone.

pub const fn public_mut(&mut self) -> &mut P

Returns the public zone for mutation inside apply.

pub fn insert_private(&mut self, player: PlayerId, value: Q) -> Option<Q>

Sets player’s private zone, returning the previous value if any.

pub fn private(&self, player: PlayerId) -> Option<&Q>

Returns player’s private zone, or None if they have none.

pub fn private_mut(&mut self, player: PlayerId) -> Option<&mut Q>

Returns a mutable reference to player’s private zone.

pub fn remove_private(&mut self, player: PlayerId) -> Option<Q>

Removes and returns player’s private zone, if any.

Needed to reverse a deal exactly: undoing a chance move that dealt a private card must leave no stale entry behind, so a Reversible::undo calls this to drop the card it handed out.

Example

use turnbase::{PlayerId, State};
let mut state: State<(), u8> = State::new((), 0);
state.insert_private(PlayerId::new(0), 7); // deal
assert_eq!(state.remove_private(PlayerId::new(0)), Some(7)); // undo the deal
assert_eq!(state.private(PlayerId::new(0)), None);

pub const fn rng(&self) -> &Prng

Returns the match’s generator.

pub const fn rng_mut(&mut self) -> &mut Prng

Returns the match’s generator for drawing randomness inside apply.

impl<P: Clone, Q: Clone> State<P, Q>

pub fn view_for(&self, viewer: Option<PlayerId>) -> PlayerView<P, Q>

Produces the standard observation for viewer: the public zone plus their own private zone (None viewer, a spectator, sees public only).

This is the default visibility rule. Games whose rule is inverted or otherwise non-standard (e.g. Hanabi) build their PlayerView directly instead of calling this. Clones the observed data, so games with a large public zone may prefer a cheaper custom projection.

Trait Implementations

impl<P: Clone, Q: Clone> Clone for State<P, Q>

fn clone(&self) -> State<P, Q>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<P: Debug, Q: Debug> Debug for State<P, Q>

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

Formats the value using the given formatter.

impl<'de, P, Q> Deserialize<'de> for State<P, Q>

where P: Deserialize<'de>, Q: Deserialize<'de>,

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<P: PartialEq, Q: PartialEq> PartialEq for State<P, Q>

fn eq(&self, other: &State<P, Q>) -> 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<P, Q> Serialize for State<P, Q>

where P: Serialize, Q: Serialize,

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<P: Eq, Q: Eq> Eq for State<P, Q>

impl<P, Q> StructuralPartialEq for State<P, Q>