Struct MemScratch 

pub struct MemScratch { /* private fields */ }

In-memory Scratch: a growable buffer that “freezes” to a borrow of itself. The reference implementation — it backs tests, and because it drives the streaming path with no files it is the vehicle for the disk_first == in_memory property test. It stages in RAM, so it does not save RAM; a host Scratch over a temp file is what bounds RAM in practice.

Implementations

impl MemScratch

pub fn new() -> Self

An empty staging buffer.

Trait Implementations

impl Clone for MemScratch

fn clone(&self) -> MemScratch

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MemScratch

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

Formats the value using the given formatter.

impl Default for MemScratch

fn default() -> MemScratch

Returns the “default value” for a type.

impl Scratch for MemScratch

type Error = Infallible

Implementation-specific failure (I/O error, host callback error…).

fn write(&mut self, bytes: &[u8]) -> Result<(), Self::Error>

Appends bytes to the staging area. Not to be called after freeze.

fn len(&self) -> u64

Bytes appended so far.

fn freeze(&mut self) -> Result<&[u8], Self::Error>

Ends the build and borrows everything written as one contiguous slice, for random and sequential reads (a file backing typically maps itself here). The borrow keeps the region alive, which is also what forbids a later write.

fn is_empty(&self) -> bool

Whether nothing has been written yet.