Struct ScanBuffer 

pub struct ScanBuffer { /* private fields */ }

A refillable buffer for streaming JSON parsing.

Uses a grow-only strategy: we either reset (when all data processed) or grow (when mid-token). Never compacts/shifts data.

Implementations

impl ScanBuffer

pub fn new() -> Self

Create a new buffer with the default capacity.

pub fn with_capacity(capacity: usize) -> Self

Create a new buffer with a specific capacity.

pub fn from_slice(slice: &[u8]) -> Self

Create a buffer from an existing slice (for slice-based parsing).

pub fn data(&self) -> &[u8]

Get the current buffer contents.

pub fn is_eof(&self) -> bool

Whether the underlying reader has reached EOF.

pub fn filled(&self) -> usize

How many bytes are filled.

pub fn capacity(&self) -> usize

Get the buffer’s total capacity.

pub fn reset(&mut self)

Reset the buffer for fresh data.

Called when all data has been processed (scanner returned Eof but reader has more). This is NOT compaction - we’re simply starting fresh because everything was consumed.

pub fn grow(&mut self)

Grow the buffer to make room for more data.

Called when mid-token (NeedMore) and buffer is full. We grow rather than compact because:

• No data copying needed
• Scanner indices remain valid
• Simpler logic

pub fn refill<R: Read>(&mut self, reader: &mut R) -> Result<usize>

Refill the buffer from a synchronous reader.

Reads more data into the unfilled portion of the buffer. Returns the number of bytes read, or 0 if EOF.

Trait Implementations

impl Debug for ScanBuffer

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

Formats the value using the given formatter.

impl Default for ScanBuffer

fn default() -> Self

Returns the “default value” for a type.