Struct scale_info::Variant

pub struct Variant<T: Form = MetaForm> { /* fields omitted */ }

A struct enum variant with either named (struct) or unnamed (tuple struct) fields.

Example

enum Operation {
    Zero,
//  ^^^^ this is a unit struct enum variant
    Add(i32, i32),
//  ^^^^^^^^^^^^^ this is a tuple-struct enum variant
    Minus { source: i32 }
//  ^^^^^^^^^^^^^^^^^^^^^ this is a struct enum variant
}

Implementations

impl Variant

pub fn with_fields<F>(name: &'static str, fields: FieldsBuilder<F>) -> Self

Creates a new variant with the given fields.

pub fn with_discriminant(name: &'static str, discriminant: u64) -> Self

Creates a new variant with the given discriminant.

impl<T> Variant<T> where
    T: Form, 

pub fn name(&self) -> &T::String

Returns the name of the variant

pub fn fields(&self) -> &[Field<T>]

Returns the fields of the struct variant.

pub fn discriminant(&self) -> Option<u64>

Returns the discriminant of the variant.

Trait Implementations

impl<T: Clone + Form> Clone for Variant<T> where
    T::String: Clone, 

fn clone(&self) -> Variant<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T: Debug + Form> Debug for Variant<T> where
    T::String: Debug, 

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

Formats the value using the given formatter.

impl<T: Form> Decode for Variant<T> where
    T::String: Decode,
    T::String: Decode,
    Vec<Field<T>>: Decode,
    Vec<Field<T>>: Decode, 

fn decode<__CodecInputEdqy: Input>(
    __codec_input_edqy: &mut __CodecInputEdqy
) -> Result<Self, Error>

Attempt to deserialise the value from input.

pub fn skip<I>(input: &mut I) -> Result<(), Error> where
    I: Input, 

Attempt to skip the encoded value from input.

pub fn encoded_fixed_size() -> Option<usize>

Returns the fixed encoded size of the type.

impl<T: Form> Encode for Variant<T> where
    T::String: Encode,
    T::String: Encode,
    Vec<Field<T>>: Encode,
    Vec<Field<T>>: Encode, 

fn encode_to<__CodecOutputEdqy: Output + ?Sized>(
    &self,
    __codec_dest_edqy: &mut __CodecOutputEdqy
)

Convert self to a slice and append it to the destination.

pub fn size_hint(&self) -> usize

If possible give a hint of expected size of the encoding.

pub fn encode(&self) -> Vec<u8, Global>

Convert self to an owned vector.

pub fn using_encoded<R, F>(&self, f: F) -> R where
    F: FnOnce(&[u8]) -> R, 

Convert self to a slice and then invoke the given closure with it.

pub fn encoded_size(&self) -> usize

Calculates the encoded size.

impl<T: Form> EncodeLike<Variant<T>> for Variant<T> where
    T::String: Encode,
    T::String: Encode,
    Vec<Field<T>>: Encode,
    Vec<Field<T>>: Encode, 

impl<T: Eq + Form> Eq for Variant<T> where
    T::String: Eq, 

impl IntoPortable for Variant

type Output = Variant<PortableForm>

The portable version of Self.

fn into_portable(self, registry: &mut Registry) -> Self::Output

Convert self to the portable form by using the registry for caching.

impl<T: Ord + Form> Ord for Variant<T> where
    T::String: Ord, 

fn cmp(&self, other: &Variant<T>) -> Ordering

This method returns an Ordering between self and other.

#[must_use]pub fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

#[must_use]pub fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

#[must_use]pub fn clamp(self, min: Self, max: Self) -> Self

Restrict a value to a certain interval.

impl<T: PartialEq + Form> PartialEq<Variant<T>> for Variant<T> where
    T::String: PartialEq, 

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

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Variant<T>) -> bool

This method tests for !=.

impl<T: PartialOrd + Form> PartialOrd<Variant<T>> for Variant<T> where
    T::String: PartialOrd, 

fn partial_cmp(&self, other: &Variant<T>) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Variant<T>) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Variant<T>) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Variant<T>) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Variant<T>) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<T: Form> StructuralEq for Variant<T>

impl<T: Form> StructuralPartialEq for Variant<T>