Trait Source 

pub trait Source {
    type Volatility: Volatility;

    const UTF8: bool;
    const INSITU: bool;
    const NULL_PADDED: bool;

    // Required methods
    fn ptr(&mut self, offset: usize) -> *const u8;
    fn ptr_mut(&mut self, offset: usize) -> *mut u8;
    fn trim(&mut self, until: usize);
    fn len(&mut self) -> usize;
}

Trait representing a source of JSON data for parsing.

This trait abstracts over different input types, allowing the parser to work with strings, byte slices, and streaming readers uniformly.

Required Associated Constants

const UTF8: bool

Whether the source is guaranteed to be valid UTF-8.

When false, the parser will validate UTF-8 encoding for JSON string values.

Note: Validation is limited to strings only, as invalid UTF-8 elsewhere in the JSON will be rejected as an unexpected token during parsing.

const INSITU: bool

Whether the source allows in-situ (in-place) parsing.

In-situ parsing modifies the source data directly to parse strings. Requires the source to be non volatile as well.

const NULL_PADDED: bool

Whether the source is 64 null bytes padded at the end. Allows the parser to skip bounds checking.

Safety

The source must be non volatile. As the parser will store and use the pointer as index.

Required Associated Types

type Volatility: Volatility

The volatility of the source.

Required Methods

fn ptr(&mut self, offset: usize) -> *const u8

Returns a pointer at the given offset.

Safety

The parser ensures the offset is within bounds by checking len() beforehand. Implementations must not panic.

fn ptr_mut(&mut self, offset: usize) -> *mut u8

Returns a mutable pointer to the byte at the given offset.

This method is used for in-situ parsing. Implementations may return a null pointer or use unimplemented!()/unreachable() if INSITU is false. The parser only calls this method when in-situ parsing conditions are met.

Safety

The parser ensures the offset is within bounds by checking len() beforehand. Implementations must not panic.

fn trim(&mut self, until: usize)

Signal to discard data up to the given offset (exclusive).

This method is only called for volatile sources to free memory as data is consumed.

fn len(&mut self) -> usize

Returns the current length of available source data in bytes.

The parser requires at least 64 bytes of data to be available during parsing, otherwise it may give false EOF-related errors.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl Source for &str

const UTF8: bool = true

const INSITU: bool = false

const NULL_PADDED: bool = false

type Volatility = NonVolatile

fn ptr(&mut self, offset: usize) -> *const u8

fn ptr_mut(&mut self, _: usize) -> *mut u8

fn trim(&mut self, _: usize)

fn len(&mut self) -> usize

impl Source for &mut str

const UTF8: bool = true

const INSITU: bool = true

const NULL_PADDED: bool = false

type Volatility = NonVolatile

fn ptr(&mut self, offset: usize) -> *const u8

fn ptr_mut(&mut self, offset: usize) -> *mut u8

fn trim(&mut self, _: usize)

fn len(&mut self) -> usize

Implementors

impl Source for &NullPadded

const UTF8: bool = true

const INSITU: bool = false

const NULL_PADDED: bool = true

type Volatility = NonVolatile

impl Source for &mut NullPadded

const UTF8: bool = true

const INSITU: bool = true

const NULL_PADDED: bool = true

type Volatility = NonVolatile

impl<const UTF8: bool, R: Read> Source for Reader<R, UTF8>

const UTF8: bool = UTF8

const INSITU: bool = false

const NULL_PADDED: bool = false

type Volatility = Volatile