Crate integer_encoding

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Expand description

Fast serialization of integers.

This crate implements encoding and decoding of integer types to and from FixedInt (i.e. a representation of integers similar or equal to how they are stored in memory) as well as VarInt (encoding integers so that they only use as much memory as needed to represent their magnitude).

This is useful when (de)serializing data from and to binary representations. For example, Protocol Buffers (by Google) use these kinds of encoding.

use integer_encoding::*;

fn main() {
    let a: u32 = 344;
    let encoded_byte_slice = a.encode_fixed_light();
    assert_eq!(a, u32::decode_fixed(encoded_byte_slice));
    assert_eq!(4, encoded_byte_slice.len());

    let b: i32 = -111;
    let encoded_byte_vec = b.encode_var_vec();
    assert_eq!(Some((b, 2)), i32::decode_var(&encoded_byte_vec));
}

Traitsยง

  • FixedInt provides encoding/decoding to and from fixed int representations.
  • A trait for reading FixedInts from any other Reader.
  • A trait for writing integers without encoding (i.e. FixedInt) to any Write type.
  • Varint (variable length integer) encoding, as described in https://developers.google.com/protocol-buffers/docs/encoding.
  • A trait for reading VarInts from any other Reader.
  • A trait for writing integers in VarInt encoding to any Write type. This packs encoding and writing into one step.