Struct Deserializer 

pub struct Deserializer<'a> { /* private fields */ }

Deserializes a serializable from JSON.

Every call to deserialize reads the next value. What may follow a value is controlled by DeserializerConfig::set_trailing. By default only whitespace may follow so there is only a single value. With Trailing::Newline the deserializer reads JSON Lines:

use deser_jsonc::{
    Deserializer, DeserializerConfig, Trailing,
};

let config = DeserializerConfig::builder().trailing(Trailing::Newline).build();
let mut de =
    Deserializer::from_str_with_config("[1, 2]\n[3]\n", config);
assert_eq!(de.deserialize::<Vec<u32>>().unwrap(), [1, 2]);
assert_eq!(de.deserialize::<Vec<u32>>().unwrap(), [3]);
assert!(de.is_end());

To deserialize a single value, use from_str and from_slice (or the methods of the same name on DeserializerConfig). The deserializer is also useful to drive a custom sink.

Implementations

impl<'a> Deserializer<'a>

pub fn from_str(input: &'a str) -> Deserializer<'a>

Creates a new deserializer for a string.

pub fn from_str_with_config( input: &'a str, config: DeserializerConfig, ) -> Deserializer<'a>

Creates a new deserializer for a string with the given configuration.

pub fn from_slice(input: &'a [u8]) -> Deserializer<'a>

Creates a new deserializer for a byte slice.

The input is not validated upfront. Instead strings are validated as UTF-8 when they are parsed (bytes outside of strings are only ever accepted if they are ASCII). Invalid UTF-8 is an error.

pub fn from_slice_with_config( input: &'a [u8], config: DeserializerConfig, ) -> Deserializer<'a>

Creates a new deserializer for a byte slice with the given configuration.

See from_slice.

pub fn config(&self) -> &DeserializerConfig

Returns the configuration.

pub fn offset(&self) -> usize

Returns the current offset in the input.

pub fn is_end(&self) -> bool

Returns true if there are no more values.

This is the case if only whitespace is left or if a value failed and the stream cannot be continued (see deserialize).

pub fn end(&self) -> Result<(), Error>

Fails if there is more than whitespace left.

This is useful with Trailing::Stop to check that the input was consumed.

pub fn deserialize<T: Deserialize<'a>>(&mut self) -> Result<T, Error>

Deserializes the next value.

What may follow the value depends on DeserializerConfig::set_trailing. Fails with ErrorKind::EndOfFile if there are no more values.

If a value fails to deserialize (because it’s malformed or does not match the type), the stream ends: is_end returns true and further calls fail. With Trailing::Newline only the rest of the line is skipped and the next call continues with the next line.

To configure the deserialization (for instance to add layers) use deserialize_with.

pub fn deserialize_with<T, F>(&mut self, setup: F) -> Result<T, Error>

where T: Deserialize<'a>, F: FnOnce(&mut DeserializeDriver<'_, 'a>),

Deserializes the next value with a configured driver.

The callback is invoked with the driver before the value is deserialized, for instance to add Layers.

pub fn iter<T: Deserialize<'a>>(&mut self) -> Iter<'_, 'a, T>

Returns an iterator over the remaining values.

This is useful to read JSON Lines (see Trailing::Newline). The iterator stops after the first error.

use deser_jsonc::{
    Deserializer, DeserializerConfig, Trailing,
};

let config = DeserializerConfig::builder().trailing(Trailing::Newline).build();
let mut de = Deserializer::from_str_with_config("1\n2\n3\n", config);
let items = de.iter::<u32>().collect::<Result<Vec<_>, _>>().unwrap();
assert_eq!(items, [1, 2, 3]);

pub fn drive( &mut self, driver: &mut DeserializeDriver<'_, 'a>, ) -> Result<(), Error>

Parses the next value and feeds the events into the given driver.

This is useful to deserialize into a custom Sink. See also deserialize_with.

Strings without escape sequences are passed on borrowed from the input (see emit_borrowed). Errors carry the location in the input (see Error::line).

The context of the configuration is given to the driver (values that the context of the driver has take precedence, see DeserializeDriver::set_default_context).

Trait Implementations

impl<'a> Deserializer<'a> for Deserializer<'a>

fn drive(&mut self, driver: &mut DeserializeDriver<'_, 'a>) -> Result<(), Error>

Parses the input and feeds the events of a value into the driver.

fn deserialize<T>(&mut self) -> Result<T, Error>

where T: Deserialize<'de>, Self: Sized,

Deserializes a value.

fn deserialize_with<T, F>(&mut self, setup: F) -> Result<T, Error>

where T: Deserialize<'de>, F: FnOnce(&mut DeserializeDriver<'_, 'de>), Self: Sized,

Deserializes a value with a configured driver.

fn update<T>(&mut self, value: &mut T) -> Result<(), Error>

where T: Deserialize<'de>, Self: Sized,

Updates an existing value with the next value.

fn update_with<T, F>(&mut self, value: &mut T, setup: F) -> Result<(), Error>

where T: Deserialize<'de>, F: FnOnce(&mut DeserializeDriver<'_, 'de>), Self: Sized,

Updates an existing value with the next value after setting up the driver.