# Trait serde::ser::SerializeStructVariant

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    pub trait SerializeStructVariant {
        type Ok;
        type Error: Error;

        fn serialize_field<T: ?Sized>(
            &mut self,
            key: &'static str,
            value: &T
        ) -> Result<(), Self::Error>
        where
            T: Serialize;
        fn end(self) -> Result<Self::Ok, Self::Error>;

        fn skip_field(&mut self, key: &'static str) -> Result<(), Self::Error> { ... }
    }

Expand description

Returned from `Serializer::serialize_struct_variant`.

## Example use

ⓘ

    use serde::ser::{Serialize, SerializeStructVariant, Serializer};

    enum E {
        S { r: u8, g: u8, b: u8 },
    }

    impl Serialize for E {
        fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
        where
            S: Serializer,
        {
            match *self {
                E::S {
                    ref r,
                    ref g,
                    ref b,
                } => {
                    let mut sv = serializer.serialize_struct_variant("E", 0, "S", 3)?;
                    sv.serialize_field("r", r)?;
                    sv.serialize_field("g", g)?;
                    sv.serialize_field("b", b)?;
                    sv.end()
                }
            }
        }
    }

## Example implementation

The example data format presented on the website demonstrates an implementation of `SerializeStructVariant` for a basic JSON data format.

## Required Associated Types

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#### type Ok

Must match the `Ok` type of our `Serializer`.

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#### type Error: Error

Must match the `Error` type of our `Serializer`.

## Required Methods

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#### fn serialize_field<T: ?Sized>(
&mut self,
key: &'static str,
value: &T
) -> Result<(), Self::Error> where
T: Serialize,

Serialize a struct variant field.

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#### fn end(self) -> Result<Self::Ok, Self::Error>

Finish serializing a struct variant.

## Provided Methods

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#### fn skip_field(&mut self, key: &'static str) -> Result<(), Self::Error>

Indicate that a struct variant field has been skipped.

## Implementors

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### impl<Ok, Error> SerializeStructVariant for Impossible<Ok, Error> where
Error: Error,

#### type Ok = Ok

#### type Error = Error