Struct VarInt 

pub struct VarInt(pub i32);

A variable-length encoded 32-bit signed integer, occupying 1 to 5 bytes.

VarInt is the most common type in the Minecraft protocol. It is used for packet IDs, packet lengths, string length prefixes, array lengths, enum discriminants, and many field values. The encoding uses the MSB of each byte as a continuation bit (1 = more bytes follow, 0 = last byte), with the lower 7 bits carrying the value in little-endian order (least significant group first). Negative values use two’s complement and always require 5 bytes.

Tuple Fields

0: i32

Implementations

impl VarInt

pub const MAX_BYTES: usize = 5

Maximum number of bytes a VarInt can occupy on the wire.

Trait Implementations

impl Clone for VarInt

fn clone(&self) -> VarInt

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for VarInt

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

Formats the value using the given formatter.

impl Decode for VarInt

Decodes a VarInt by reading 1-5 bytes from the buffer.

Reads bytes one at a time, accumulating 7-bit groups until a byte without the continuation bit is found. If more than 5 bytes have the continuation bit set, the value would exceed 32 bits and the decoder returns Error::VarIntTooLarge. If the buffer runs out mid-VarInt, returns Error::BufferUnderflow.

fn decode(buf: &mut &[u8]) -> Result<Self>

Reads and decodes a VarInt, advancing the cursor past all consumed bytes.

impl Encode for VarInt

Encodes the VarInt as 1-5 bytes using MSB continuation bit encoding.

Each byte carries 7 bits of the value (least significant first). The MSB is set to 1 if more bytes follow, 0 on the final byte. Negative values are encoded as their unsigned two’s complement representation and always produce 5 bytes.

fn encode(&self, buf: &mut Vec<u8>) -> Result<()>

Writes the variable-length encoded bytes to the buffer.

impl EncodedSize for VarInt

Computes the number of bytes this VarInt will occupy when encoded.

Returns 1-5 based on the unsigned magnitude of the value. Small positive values (0-127) take 1 byte, while negative values always take 5 bytes due to two’s complement sign extension.

fn encoded_size(&self) -> usize

impl From<VarInt> for i32

Extracts the inner i32 value from a VarInt.

fn from(value: VarInt) -> Self

Converts to this type from the input type.

impl From<i32> for VarInt

Wraps a raw i32 into a VarInt for protocol encoding.

fn from(value: i32) -> Self

Converts to this type from the input type.

impl Hash for VarInt

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 PartialEq for VarInt

fn eq(&self, other: &VarInt) -> 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 Copy for VarInt

impl Eq for VarInt

impl StructuralPartialEq for VarInt