[−][src]Crate varint_rs
Varint is an alternative way of storing integer numbers.
Varints allow for the storage of larger integer types in a smaller amount of
space. It does this by storing an integer using the 7 lower bits and a flag
in the most-significant bit. This flag is set to 1 when more bytes should
be read. The groups of 7 bits are then added from the least-significant
group first.
Example
// to allow the use of the `VarintWriter::write_*_varint` functions use varint_rs::VarintWriter; // to allow the use of the `VarintReader::read_*_varint` functions use varint_rs::VarintReader; // an example to use for the buffer use std::io::Cursor; // create an i32 set to `300` let number: i32 = 300; // create a buffer for the varint to be writen to // an i32 can be `4` bytes maximum, so we pre-allocate the capacity let mut buffer: Cursor<Vec<u8>> = Cursor::new(Vec::with_capacity(4)); // now we can write the varint into the buffer // `300` should only use `2` bytes instead of all `4` // the `write_*_varint` functions may return an `std::io::Error` buffer.write_i32_varint(number).unwrap(); // we reset the cursor pos back to `0`, this isn't varint stuff buffer.set_position(0); // now we can read the varint from the buffer // we should read `300` which was the number we stored // the `read_*_varint` functions may return an `std::io::Error` let number: i32 = buffer.read_i32_varint().unwrap();
Re-exports
pub use zigzag::Zigzag; |
Modules
| zigzag | Zigzag encoding is an alternative way of encoding negative numbers. |
Traits
| VarintReader | The |
| VarintWriter | The |