Enum EffectHost 

pub enum EffectHost {
    Battler(BattlerRef),
    Side(u8),
    Field,
}

Where an effect is hosted (design §3.1, the broadened addressing). A cross-gen battle hosts effects not only on a battler (volatiles, ability, item) but on a side (screens, hazards, Wish) or the field (weather, terrain, Trick Room). EffectHost is the 3-way scope the engine routes by.

Non-breaking note (design §3.1, §7)

The design’s §3.1 sketch proposed widening the EffectState.host field from BattlerRef to EffectHost “via From<BattlerRef> so existing constructors compile unchanged.” In Rust that does not hold for struct-literal field initialization (EffectState { host: who, .. } and the field-shorthand host,): field init requires the exact field type and never invokes From/Into. Widening the field would therefore force an edit to all 40+ Gen-1 slice construction sites — a NO-GO on the design’s own “Non-breaking” axis (§6.2). See the returned findings for the documented NO-GO.

So EffectHost ships as an additive type: EffectState.host stays BattlerRef (battler-hosted effects, the only kind the engine fires today — every slice compiles verbatim), and EffectState::host_scope projects it to EffectHost::Battler. Side- and field-hosted state is addressed through the EffectHost::Side/Field cases and the defaulted side_effects/ field_effects resolvers (the game owns that mutable state). From and PartialEq cross-impls let routing code treat a BattlerRef and an EffectHost::Battler interchangeably.

Variants

Battler(BattlerRef)

Hosted on one battler (volatile, ability, item).

Side(u8)

Hosted on a side (screens, hazards, Wish). 0 = player, 1 = opponent.

Field

Hosted on the field (weather, terrain, Trick Room).

Trait Implementations

impl Clone for EffectHost

fn clone(&self) -> EffectHost

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for EffectHost

impl Debug for EffectHost

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

Formats the value using the given formatter.

impl Eq for EffectHost

impl From<BattlerRef> for EffectHost

fn from(r: BattlerRef) -> Self

Converts to this type from the input type.

impl PartialEq for EffectHost

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

Equality operator ==.

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

Inequality operator !=.

impl PartialEq<BattlerRef> for EffectHost

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

Equality operator ==.

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

Inequality operator !=.

impl PartialEq<EffectHost> for BattlerRef

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for EffectHost