Struct IonCAnnotationsFieldWriterContext

pub struct IonCAnnotationsFieldWriterContext<'b, 'c, T: IonCAnnotationsFieldWriter + ?Sized> { /* private fields */ }

Context for writing annotations and fields in with proper reference lifetimes.

Specifically, writing annotations and fields with Ion C with ion_writer_write_annotations/ion_writer_add_annotation and ion_writer_write_field is particularly problematic because the lifetime of the ION_STRING passed into that function, must be valid until a corresponding ion_writer_write_* function is called for writing a value.

This context tracks the lifetime of the string slices that a user wants to write as annotations and the field name along with a mutable borrow of the writer handle and ensures that calls to ion_writer_add_annotation/ion_writer_write_field happen before invoking the ion_writer_write_* call for the value in a lifetime correct way.

Note that this context can be thought of as a partial function for writing annotations and/or struct fields, so doing nothing with it is simply a no-op, and performing multiple IonCValueWriter trait method invocations is the same as writing the field before invoking the value writing methods (so duplicate fields would be generated in that case).

Implementations

impl<'b, 'c, T: IonCAnnotationsFieldWriter + ?Sized> IonCAnnotationsFieldWriterContext<'b, 'c, T>

pub fn annotations(&mut self, annotations: &'c [&'c str]) -> &mut Self

Sets the annotations for the context.

pub fn field(&mut self, field: &'c str) -> &mut Self

Sets the field name for the context.

Trait Implementations

impl<T: IonCAnnotationsFieldWriter + ?Sized> IonCValueWriter for IonCAnnotationsFieldWriterContext<'_, '_, T>

fn finish_container(&mut self) -> IonCResult<()>

This API is not relevant for this context and will always return an error.

fn write_null(&mut self, tid: ION_TYPE) -> IonCResult<()>

Writes a null value.

fn write_bool(&mut self, value: bool) -> IonCResult<()>

Writes a bool value.

fn write_i64(&mut self, value: i64) -> IonCResult<()>

Writes an int value.

fn write_bigint(&mut self, value: &BigInt) -> IonCResult<()>

Writes an int value.

fn write_f64(&mut self, value: f64) -> IonCResult<()>

Writes a float value.

fn write_bigdecimal(&mut self, value: &BigDecimal) -> IonCResult<()>

Writes a decimal value.

fn write_datetime(&mut self, value: &IonDateTime) -> IonCResult<()>

Writes a timestamp value.

fn write_symbol(&mut self, value: &str) -> IonCResult<()>

Writes a symbol value.

fn write_string(&mut self, value: &str) -> IonCResult<()>

Writes a string value.

fn write_clob(&mut self, value: &[u8]) -> IonCResult<()>

Writes a clob value.

fn write_blob(&mut self, value: &[u8]) -> IonCResult<()>

Writes a blob value.

fn start_container(&mut self, tid: ION_TYPE) -> IonCResult<()>

Starts a container.