Trait VariantBuilderExt 

pub trait VariantBuilderExt {
    type State<'a>: BuilderSpecificState + 'a
       where Self: 'a;

    // Required methods
    fn append_null(&mut self);
    fn append_value<'m, 'v>(&mut self, value: impl Into<Variant<'m, 'v>>);
    fn try_new_list(
        &mut self,
    ) -> Result<ListBuilder<'_, Self::State<'_>>, ArrowError>;
    fn try_new_object(
        &mut self,
    ) -> Result<ObjectBuilder<'_, Self::State<'_>>, ArrowError>;

    // Provided methods
    fn new_list(&mut self) -> ListBuilder<'_, Self::State<'_>> { ... }
    fn new_object(&mut self) -> ObjectBuilder<'_, Self::State<'_>> { ... }
}

Extends VariantBuilder to help building nested Variants

Allows users to append values to a VariantBuilder, ListBuilder or ObjectBuilder. using the same interface.

Required Associated Types

type State<'a>: BuilderSpecificState + 'a where Self: 'a

The builder specific state used by nested builders

Required Methods

fn append_null(&mut self)

Appends a NULL value to this builder. The semantics depend on the implementation, but will often translate to appending a Variant::Null value.

fn append_value<'m, 'v>(&mut self, value: impl Into<Variant<'m, 'v>>)

Appends a new variant value to this builder. See e.g. VariantBuilder::append_value.

fn try_new_list( &mut self, ) -> Result<ListBuilder<'_, Self::State<'_>>, ArrowError>

Creates a nested list builder. See e.g. VariantBuilder::new_list. Returns an error if the nested builder cannot be created, see e.g. ObjectBuilder::try_new_list.

fn try_new_object( &mut self, ) -> Result<ObjectBuilder<'_, Self::State<'_>>, ArrowError>

Creates a nested object builder. See e.g. VariantBuilder::new_object. Returns an error if the nested builder cannot be created, see e.g. ObjectBuilder::try_new_object.

Provided Methods

fn new_list(&mut self) -> ListBuilder<'_, Self::State<'_>>

Creates a nested list builder. See e.g. VariantBuilder::new_list. Panics if the nested builder cannot be created, see e.g. ObjectBuilder::new_list.

fn new_object(&mut self) -> ObjectBuilder<'_, Self::State<'_>>

Creates a nested object builder. See e.g. VariantBuilder::new_object. Panics if the nested builder cannot be created, see e.g. ObjectBuilder::new_object.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementors

impl VariantBuilderExt for VariantArrayBuilder

type State<'a> = ArrayBuilderState<'a> where VariantArrayBuilder: 'a

impl VariantBuilderExt for VariantBuilder

type State<'a> = () where VariantBuilder: 'a

impl<'a, S> VariantBuilderExt for ListBuilder<'a, S>

where S: BuilderSpecificState,

type State<'s> = ListState<'s> where ListBuilder<'a, S>: 's

impl<S> VariantBuilderExt for ObjectFieldBuilder<'_, '_, '_, S>

where S: BuilderSpecificState,

type State<'a> = ObjectState<'a> where ObjectFieldBuilder<'_, '_, '_, S>: 'a