|0.1.2||Feb 13, 2022|
|0.1.1||Oct 26, 2020|
|0.1.0||Apr 16, 2019|
#1752 in Procedural macros
22 downloads per month
Used in blynk_io
restruct is used to interpret binary data stored in files or other sources or convert
between C structs and Rust types and when using a parser-generator is considered
It is a brainchild of Python's struct-module.
The library uses Format Strings as compact descriptions of the binary data and the intended conversion to/from Rust-types. The Format Strings are interpreted at compile-time to generate a type whose functions can be used to convert between unstructured and structured data.
// Generate a parser in little-endian for two 32bit integers, a float and a bool. #[derive(restruct_derive::Struct)] #[fmt="<2if?"] struct FooParser; // Pack a tuple of two integers, a float and a bool into a [u8; _]-buffer. let packed = FooParser::pack((1, 2, 3.0, false)); assert_eq!(packed, [1, 0, 0, 0, 2, 0, 0, 0, 0, 0, 64, 64, 0]); assert_eq!(packed.len(), FooParser::SIZE); // Packing and unpacking can't fail at runtime. let unpacked = FooParser::unpack(packed); assert_eq!(unpacked, (1, 2, 3.0, false)); // Any `io::Read` can be used directly. let unpacked = FooParser::read_from(&mut &packed[..]).expect("i/o failed"); assert_eq!(unpacked, (1, 2, 3.0, false)); // Any `io::Write` can be used directly. let mut buffer = Vec::with_capacity(FooParser::SIZE); FooParser::write_to((1, 2, 3.0, false), &mut buffer).expect("i/o failed"); assert_eq!(&buffer, &packed);
// Because packing and unpacking is const we can use these functions to initialize other consts const TEAPOT: <Tea as restruct::Struct>::Unpacked = Tea::unpack(*include_bytes!("teapot.bin")); const TEAPOT_TEMPERATURE: i32 = TEAPOT.0; const TEAPOT_FILL_STATUS: f32 = TEAPOT.2; const TEAPOT_ACTIVE: bool = TEAPOT.3;