Struct PortableExtensions 

pub struct PortableExtensions(/* private fields */);

A bag of preserved (key, value) pairs, in the document’s own vocabulary.

Used for both channels (see the module docs): the nested extensions object this build writes, and the flattened catch-all it only reads. A newtype over a JSON value map, rather than a bare Map, so the one inserter is private and every write goes through PortableTimeDocument::insert_extension. A JSON map (not a YAML map) because this document is JSON and a YAML value JSON cannot carry is withheld and diagnosed rather than silently reshaped. The map is sorted (serde_json’s preserve_order feature is off), so key order is normalised while the values — the thing a round trip preserves — are kept exactly.

No public route to a key that could shadow a projected field

Deserialize is derived (a document has to be readable), so a caller can obtain a bag naming any key. What a caller cannot do is hand one to a flattened channel: those fields are private everywhere they exist, and the only public way in is the checked nesting shown below, where the key lands inside an object of its own and can therefore never duplicate — or be read in place of — the value beside it. That is a compile-time property, so it is asserted as one:

use tix::time_tracking::portable::{PortableExtensions, PortableTimeDocument};

let mut document: PortableTimeDocument = unimplemented!();
// The catch-all is private: there is no public field to drop a shadowing key into.
document.unknown = PortableExtensions::default();

The nested channel, for contrast, is checked rather than forbidden:

use tix::time_tracking::portable::{PortableTimeDocument, FORMAT};
use serde_json::json;

let mut document: PortableTimeDocument = unimplemented!();
document.insert_extension("format", json!("metadata, not a marker"));
let _ = FORMAT;

Implementations

impl PortableExtensions

pub fn new() -> Self

An empty bag.

pub fn is_empty(&self) -> bool

Whether no metadata is present.

pub fn len(&self) -> usize

The number of preserved keys.

pub fn get(&self, key: &str) -> Option<&Value>

Look up a preserved key.

pub fn keys(&self) -> impl Iterator<Item = &str>

The preserved keys, in canonical (sorted) order.

pub fn as_map(&self) -> &Map<String, Value>

The underlying map, for a caller that must inspect it whole.

Trait Implementations

impl Clone for PortableExtensions

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for PortableExtensions

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

Formats the value using the given formatter.

impl Default for PortableExtensions

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for PortableExtensions

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for PortableExtensions

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for PortableExtensions

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for PortableExtensions