Struct fdb_rl_proto::fdb_rl::key_expression::v1::field::FieldNullInterpretation

pub struct FieldNullInterpretation {
    pub field_null_interpretation: Option<FieldNullInterpretation>,
}

Field presence is the notion of whether a protobuf field has a value [1]. As of release 3.15, in proto3, the default is explicit presence, which is managed by optional label.

NOTE: We only support proto3 explicit presence discipline.

Following table outlines how presence is tracked for fields in proto3 [2]. (Note: ‘Singular bool’ field type is missing in the link, but has been added in the following table).

|–––––––––––––––––––––––+–––––+–––––| | Field type | optional | Explicit | | | | Presence | |–––––––––––––––––––––––+–––––+–––––| | Singular numeric (integer or floating point) | No | | | Singular enum | No | | | Singular string or bytes | No | | | Singular bool | No | | | Singular numeric (integer or floating point) | Yes | Yes | | Singular enum | Yes | Yes | | Singular string or bytes | Yes | Yes | | Singular bool | Yes | Yes | | Singular message | Yes | Yes | | Singular message | No | Yes | | Repeated | N/A | | | Oneofs | N/A | Yes | | Maps | N/A | | |–––––––––––––––––––––––+–––––+–––––|

As you can see from the above table, presence is always tracked for message and oneof. This behavior was previously used to implement optional primitive types in google/protobuf/wrappers.proto. Wrapper types is now deprecated and should not be used [3].

Under explicit presence discipline, when we have a missing value (NULL), it would be interpreted as follows.

[1]: https://protobuf.dev/programming-guides/field_presence/#background [2]: https://protobuf.dev/programming-guides/field_presence/#presence-in-proto3-apis [3]: https://cloud.google.com/apis/design/design_patterns.md#optional_primitive_fields

Fields

field_null_interpretation: Option<FieldNullInterpretation>

Required.

Trait Implementations

impl Clone for FieldNullInterpretation

fn clone(&self) -> FieldNullInterpretation

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for FieldNullInterpretation

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

Formats the value using the given formatter.

impl Default for FieldNullInterpretation

fn default() -> Self

Returns the “default value” for a type.

impl Message for FieldNullInterpretation

fn encoded_len(&self) -> usize

Returns the encoded length of the message without a length delimiter.

fn clear(&mut self)

Clears the message, resetting all fields to their default.

fn encode<B>(&self, buf: &mut B) -> Result<(), EncodeError>where B: BufMut, Self: Sized,

Encodes the message to a buffer.

fn encode_to_vec(&self) -> Vec<u8, Global>where Self: Sized,

Encodes the message to a newly allocated buffer.

fn encode_length_delimited<B>(&self, buf: &mut B) -> Result<(), EncodeError>where B: BufMut, Self: Sized,

Encodes the message with a length-delimiter to a buffer.

fn encode_length_delimited_to_vec(&self) -> Vec<u8, Global>where Self: Sized,

Encodes the message with a length-delimiter to a newly allocated buffer.

fn decode<B>(buf: B) -> Result<Self, DecodeError>where B: Buf, Self: Default,

Decodes an instance of the message from a buffer.

fn decode_length_delimited<B>(buf: B) -> Result<Self, DecodeError>where B: Buf, Self: Default,

Decodes a length-delimited instance of the message from the buffer.

fn merge<B>(&mut self, buf: B) -> Result<(), DecodeError>where B: Buf, Self: Sized,

Decodes an instance of the message from a buffer, and merges it into self.

fn merge_length_delimited<B>(&mut self, buf: B) -> Result<(), DecodeError>where B: Buf, Self: Sized,

Decodes a length-delimited instance of the message from buffer, and merges it into self.

impl PartialEq<FieldNullInterpretation> for FieldNullInterpretation

fn eq(&self, other: &FieldNullInterpretation) -> bool

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

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl ReflectMessage for FieldNullInterpretation

fn descriptor(&self) -> MessageDescriptor

Gets a MessageDescriptor describing the type of this message.

fn transcode_to_dynamic(&self) -> DynamicMessagewhere Self: Sized,

Converts this message into an instance of DynamicMessage by going through the byte representation.

impl StructuralPartialEq for FieldNullInterpretation