Struct TrackLocations 

pub struct TrackLocations(pub bool);

Asks the formats to provide the Source (a value of the Context).

Formats publish the byte range of every event, resolving them into lines and columns (for instance with the Spanned type of deser-location) also requires the source, which is a copy of the input. Formats only provide it if this is set to true in the context (or the state). The errors a deserialization fails with have their line and column either way, but for instance the keys collected with UnknownFields::Collect only have them with the source:

use deser::de::{Deserializer, IgnoredFields, UnknownFields};
use deser::{Context, Deserialize, TrackLocations};

#[derive(Deserialize)]
struct Config {
    name: String,
}

let config = deser_json::DeserializerConfig::builder()
    .context(Context::with(TrackLocations(true)))
    .build();
let input = "{\n  \"name\": \"demo\",\n  \"nmae\": \"x\"\n}";
let ignored = IgnoredFields::new();
deser_json::Deserializer::from_str_with_config(input, config)
    .deserialize_with::<Config, _>(|driver| {
        UnknownFields::Collect(ignored.clone()).set(driver.state_mut())
    })
    .unwrap();
let ignored = ignored.take();
assert_eq!((ignored[0].line(), ignored[0].column()), (Some(3), Some(3)));

Formats check this with of and set the Source before they emit the first event:

use deser::de::{DeserializeDriver, Deserializer};
use deser::{Error, Source, TrackLocations};

/// A format which provides the source if asked to.
struct Text<'a>(&'a str);

impl<'de> Deserializer<'de> for Text<'de> {
    fn drive(&mut self, driver: &mut DeserializeDriver<'_, 'de>) -> Result<(), Error> {
        if TrackLocations::of(driver.state()) {
            Source(self.0.into()).set(driver.state_mut());
        }
        driver.state_mut().set_input_range(0, self.0.len());
        driver.emit(self.0)
    }
}

Tuple Fields

0: bool

Implementations

impl TrackLocations

pub fn of(state: &State) -> bool

Returns true if the formats provide the source.

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

Sets if the formats provide the source.

Trait Implementations

impl Clone for TrackLocations

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 TrackLocations

impl Debug for TrackLocations

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

Formats the value using the given formatter.

impl Default for TrackLocations

fn default() -> Self

Returns the “default value” for a type.

impl Eq for TrackLocations

impl PartialEq for TrackLocations

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

Equality operator ==.

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

Inequality operator !=.

impl StructuralPartialEq for TrackLocations