Struct State 

pub struct State { /* private fields */ }

Everything about a scorecard that affects future play.

Only three facts matter for legality and expected value: which categories are filled, the upper-section subtotal capped at the bonus threshold of 63, and whether the Yahtzee box holds 50 (the gate for the 100-point bonus). Box-by-box history is display data and lives in Scorecard; the solver keys its value table on this type via State::index.

Implementations

impl State

pub const START: Self

The empty card at the start of a game.

pub const fn new(scored: Categories, upper: u8, yahtzee_50: bool) -> Self

Builds a state, clamping to consistency: upper is capped at what the scored upper categories can total (and at 63), and yahtzee_50 is cleared unless the Yahtzee box is scored.

pub const fn scored(self) -> Categories

The filled categories.

pub const fn upper(self) -> u8

The upper-section subtotal, capped at the bonus threshold of 63.

pub const fn yahtzee_50(self) -> bool

Whether the Yahtzee box holds 50, enabling 100-point bonuses and joker values for further Yahtzees.

pub const fn is_full(self) -> bool

Whether every category is filled and the game is over.

pub const fn index(self) -> usize

A perfect 20-bit hash: category bits, then the capped upper subtotal, then the Yahtzee-50 flag. Always below 1 << 20.

pub const fn from_index(index: usize) -> Option<Self>

Rebuilds a state from Self::index.

Returns None for indices that violate the invariants: an upper subtotal beyond what the scored upper categories can total (or beyond the 63 cap), or a Yahtzee-50 flag without the Yahtzee box scored.

pub fn legal_categories(self, dice: Dice) -> Categories

The categories dice may legally be scored in, applying joker forcing for extra Yahtzees.

Normally every open category is legal (scoring zero is always allowed). When the roll is a Yahtzee but the Yahtzee box is already filled — with 50 or zero — the forced-joker rule restricts the choice:

1. the matching upper box, if open, is the only legal category;
2. otherwise any open lower box, at full joker value;
3. otherwise any open upper box, for zero.

The result is non-empty unless the card is full.

pub fn apply(self, category: Category, dice: Dice) -> Option<ScoreDelta>

Scores dice in category: the written value, bonuses, and the next state.

Returns None if category is not in legal_categories. An extra Yahtzee scores joker values in the lower section (Full House 25, Small Straight 30, Large Straight 40, the rest the dice total) and earns the 100-point bonus whenever the Yahtzee box holds 50, even on a forced zero.

Trait Implementations

impl Clone for State

fn clone(&self) -> State

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for State

impl Debug for State

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

Formats the value using the given formatter.

impl Eq for State

impl Hash for State

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for State

fn eq(&self, other: &State) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for State