Struct Prefixed 

pub struct Prefixed<S: Source> { /* private fields */ }

A source that replays a buffered prefix before delegating to the rest.

Format sniffing needs to look at the first bytes and then hand the whole stream to a decoder, but Source is forward-only (ADR-0005) and cannot rewind. Reading the magic bytes into a prefix and putting them back in front is how sniffing stays compatible with that: nothing is re-read, and no source is required to seek.

Implementations

impl<S: Source> Prefixed<S>

pub const fn new(prefix: Vec<u8>, rest: S) -> Self

Replay prefix, then read from rest.

Trait Implementations

impl<S: Debug + Source> Debug for Prefixed<S>

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

Formats the value using the given formatter.

impl<S: Source> Source for Prefixed<S>

fn read(&mut self, buf: &mut [u8]) -> Result<usize>

Read into buf, returning the number of bytes read.

fn read_exact(&mut self, buf: &mut [u8]) -> Result<()>

Fill buf completely.