Struct ContentKey 

pub struct ContentKey(pub &'static str);

The key under which maps hold their own content.

In some formats a value is text or a map that holds the text together with more entries: the elements of XML are their text (<count>3</count>) or, if they have attributes, a map (<count unit="m">3</count> is {"@unit": "m", "$text": "3"}). Which of the two a value is depends on the input, not on the type it’s deserialized into. Formats like this set the key of the content in the State (see set), and values are then passed on in the form the type accepts:

• A type that rejects a map (like u32) receives the value of the key of the content, the other entries are skipped. If the map has no such key it receives empty text ("" as lexical atom).
• A type that rejects lexical atoms but accepts maps (like a struct) receives a map with the text under the key of the content (no entry for empty text).

Both only happen after a type rejected the value, so they cost nothing otherwise. Without the key (the default), values are passed on as they are.

use deser::de::{ContentKey, DeserializeDriver};
use deser::{Atom, Deserialize, Event};

#[derive(Deserialize, Debug, PartialEq)]
struct Price {
    #[deser(rename = "@currency")]
    currency: Option<String>,
    #[deser(rename = "$text")]
    amount: u32,
}

let mut out = None::<(u32, Price)>;
let mut driver = DeserializeDriver::new(&mut out);
ContentKey("$text").set(driver.state_mut());
driver.emit(Event::seq_start()).unwrap();
// a map for a `u32`
driver.emit(Event::map_start()).unwrap();
for text in ["@unit", "m", "$text", "3"] {
    driver.emit(Atom::Lexical(text.into())).unwrap();
}
driver.emit(Event::MapEnd).unwrap();
// text for a struct
driver.emit(Atom::Lexical("12".into())).unwrap();
driver.emit(Event::SeqEnd).unwrap();
drop(driver);
assert_eq!(out, Some((3, Price { currency: None, amount: 12 })));

Tuple Fields

0: &'static str

Implementations

impl ContentKey

pub fn of(state: &State) -> Option<&'static str>

Returns the key of the content of a deserialization if there is one.

pub fn set(self, state: &mut State)

Sets the key of the content of a deserialization.

The empty key means that there is no key of the content (the default).

Trait Implementations

impl Clone for ContentKey

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for ContentKey

impl Debug for ContentKey

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

Formats the value using the given formatter.

impl Eq for ContentKey

impl PartialEq for ContentKey

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for ContentKey