Struct BufEncoder 

pub struct BufEncoder<const CAP: usize> { /* private fields */ }

Hex-encodes bytes into the provided buffer.

This is an important building block for fast hex-encoding. Because string writing tools provided by core::fmt involve dynamic dispatch and don’t allow reserving capacity in strings buffering the hex and then formatting it is significantly faster.

The buffer has a fixed capacity specified when created. The capacity must be an even number since each byte is encoded as two hex characters.

Examples

let mut encoder = BufEncoder::<4>::new(Case::Lower);
encoder.put_byte(0xab);
assert_eq!(encoder.as_str(), "ab");

The following code doesn’t compile because of odd capacity:

let mut encoder = BufEncoder::<3>::new(Case::Lower);

Implementations

impl<const CAP: usize> BufEncoder<CAP>

pub fn new(case: Case) -> Self

Creates an empty BufEncoder that will encode bytes to hex characters in the given case.

pub fn put_byte(&mut self, byte: u8)

Encodes byte as hex and appends it to the buffer.

Panics

The method panics if the buffer is full.

pub fn put_bytes<I>(&mut self, bytes: I)

where I: IntoIterator, I::Item: Borrow<u8>,

Encodes bytes as hex and appends them to the buffer.

Panics

The method panics if the bytes wouldn’t fit the buffer.

pub fn put_bytes_min<'a>(&mut self, bytes: &'a [u8]) -> &'a [u8]

Encodes as many bytes as fit into the buffer as hex and return the remainder.

This method works just like put_bytes but instead of panicking it returns the unwritten bytes. The method returns an empty slice if all bytes were written

pub fn is_full(&self) -> bool

Returns true if no more bytes can be written into the buffer.

pub fn as_str(&self) -> &str

Returns the written bytes as a hex str.

pub fn clear(&mut self)

Resets the buffer to become empty.

pub fn space_remaining(&self) -> usize

How many bytes can be written to this buffer.

Note that this returns the number of bytes before encoding, not number of hex digits.

Trait Implementations

impl<const CAP: usize> Clone for BufEncoder<CAP>

fn clone(&self) -> BufEncoder<CAP>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<const CAP: usize> Debug for BufEncoder<CAP>

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

Formats the value using the given formatter.

impl<const CAP: usize> Default for BufEncoder<CAP>

fn default() -> Self

Returns the “default value” for a type.

impl<const CAP: usize, A: Borrow<u8>> Extend<A> for BufEncoder<CAP>

fn extend<T: IntoIterator<Item = A>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl<const CAP: usize, A: Borrow<u8>> FromIterator<A> for BufEncoder<CAP>

fn from_iter<T: IntoIterator<Item = A>>(iter: T) -> Self

Creates a value from an iterator.

impl<const CAP: usize> Hash for BufEncoder<CAP>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<const CAP: usize> PartialEq for BufEncoder<CAP>

fn eq(&self, other: &BufEncoder<CAP>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<const CAP: usize> Eq for BufEncoder<CAP>

impl<const CAP: usize> StructuralPartialEq for BufEncoder<CAP>