vint64 is an implementation of a variable-length encoding for 64-bit
little endian integers which optimizes for simplicity and performance.
This crate implements a variable-length encoding for 64-bit little endian integers (sometimes also referred to as a variable-length quantity, or "VLQ") with a number of properties which make it superior in almost every way to other variable-length integer encodings like LEB128, SQLite "Varuints", or CBOR:
- Capable of expressing the full 64-bit integer range with a maximum of 9-bytes
- Total length of a
vint64can be determined via the first byte alone
- Provides the most compact encoding possible for every value in range
- No loops required to encode/decode
Some precedent for this sort of encoding can be found in the Extensible Binary Meta Language (used by e.g. the Matroska media container format), however note that the specific type of "vint" used by that format still requires a loop to decode.
Copyright © 2019-2020 Tony Arcieri
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