Enum EnumDelta 

pub enum EnumDelta<T, D> {
    Became(T),
    Delta(D),
}

The delta of an enum: a change within a variant, or a change of variant.

T is the source enum and D its generated {Self}Delta, so deriving Delta on enum Shape gives Output = EnumDelta<Shape, ShapeDelta>. The wrapper is a type in this crate rather than an arm of the generated enum so that Became cannot collide with a variant you wrote.

Note that Became carries the source value whole. There is nothing smaller it could carry — the receiver holds a different variant, so it shares none of the new one — which is also why serializing an enum’s delta needs the enum itself to be serializable.

Variants

Became(T)

The value moved to a different variant, so here it is in full.

Delta(D)

The value stayed in its variant; this is what changed inside it.

Trait Implementations

impl<T: Clone, D: Clone> Clone for EnumDelta<T, D>

fn clone(&self) -> EnumDelta<T, D>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug, D: Debug> Debug for EnumDelta<T, D>

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

Formats the value using the given formatter.

impl<'de, T, D> Deserialize<'de> for EnumDelta<T, D>

where T: Deserialize<'de>, D: Deserialize<'de>,

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<T: Eq, D: Eq> Eq for EnumDelta<T, D>

impl<T: PartialEq, D: PartialEq> PartialEq for EnumDelta<T, D>

fn eq(&self, other: &EnumDelta<T, D>) -> bool

Equality operator ==.

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

Inequality operator !=.

impl<T, D> Serialize for EnumDelta<T, D>

where T: Serialize, D: Serialize,

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl<T: PartialEq, D: PartialEq> StructuralPartialEq for EnumDelta<T, D>