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Variant

Struct Variant 

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pub struct Variant<'a, R, Vals> {
    pub name: &'a str,
    pub fields: Composite<R, Vals>,
}
Expand description

This type represents named or unnamed composite values, and can be used to help generate EncodeAsType impls. It’s primarily used by the exported macros to do just that.

use scale_encode::{
    Error, EncodeAsType, Composite, CompositeField, Variant, TypeResolver
};

enum MyType {
   SomeField(bool),
   OtherField { foo: u64, bar: String }
}

impl EncodeAsType for MyType {
    fn encode_as_type_to<R: TypeResolver>(
        &self,
        type_id: R::TypeId,
        types: &R,
        out: &mut Vec<u8>
    ) -> Result<(), Error> {
        match self {
            MyType::SomeField(b) => Variant {
                name: "SomeField",
                fields: Composite::new([
                    (None, CompositeField::new(b)),
                ].into_iter())
            }.encode_variant_as_type_to(type_id, types, out),
            MyType::OtherField { foo, bar } => Variant {
                name: "OtherField",
                fields: Composite::new([
                    (Some("foo"), CompositeField::new(foo)),
                    (Some("bar"), CompositeField::new(bar))
                ].into_iter())
            }.encode_variant_as_type_to(type_id, types, out)
        }
    }
}

Fields§

§name: &'a str

The name of the variant we’ll try to encode into.

§fields: Composite<R, Vals>

The fields of the variant that we wish to encode.

Implementations§

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impl<'a, R, Vals> Variant<'a, R, Vals>
where R: TypeResolver + 'a, Vals: ExactSizeIterator<Item = (Option<&'a str>, CompositeField<'a, R>)> + Clone,

Source

pub fn encode_variant_as_type( &self, type_id: R::TypeId, types: &R, ) -> Result<Vec<u8>, Error>

A shortcut for Self::encode_variant_as_type_to() which internally allocates a Vec and returns it.

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pub fn encode_variant_as_type_to( &self, type_id: R::TypeId, types: &R, out: &mut Vec<u8>, ) -> Result<(), Error>

Encode the variant as the provided type to the output bytes.

Auto Trait Implementations§

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impl<'a, R, Vals> Freeze for Variant<'a, R, Vals>
where Composite<R, Vals>: Freeze,

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impl<'a, R, Vals> RefUnwindSafe for Variant<'a, R, Vals>
where Composite<R, Vals>: RefUnwindSafe,

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impl<'a, R, Vals> Send for Variant<'a, R, Vals>
where Composite<R, Vals>: Send,

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impl<'a, R, Vals> Sync for Variant<'a, R, Vals>
where Composite<R, Vals>: Sync,

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impl<'a, R, Vals> Unpin for Variant<'a, R, Vals>
where Composite<R, Vals>: Unpin,

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impl<'a, R, Vals> UnsafeUnpin for Variant<'a, R, Vals>
where Composite<R, Vals>: UnsafeUnpin,

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impl<'a, R, Vals> UnwindSafe for Variant<'a, R, Vals>
where Composite<R, Vals>: UnwindSafe,

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = !

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, !>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.