`datalit`

Overview

datalit provides the datalit!(...) macro to turn a readable list of things into real bytes—at compile time. Highlights:

Readable data: Hard to read raw byte arrays? Describe intent with readable literals.
Endian aware: Unsure about byte order? Declare it once; the macro handles the rest.
Offsets: Tired of recalculating offsets? Labels and offset expressions update themselves.
Concise: Spending time on padding & length management? Built-ins remove the manual bookkeeping.
Zero cost at runtime: Worried about hidden cost or mistakes? Your data is validated at compile time, and expands to one static slice.

Installation

datalit can be added using the standard cargo add command:

$ cargo add datalit
...

Usage

In your code, you can use a datalit macro as an expression. This will resolve to a reference to a static array that contains the data described by the contents of the macro.

Examples

use datalit::datalit;

let data = datalit!(
  // Hex / binary literals of any length (whole bytes) appended L->R.
  0xDEAD_BEEF_CAFE_BABE,
  0b0110_1111_1000_0100,

  // Primitive integers: native endian by default.
  1u32, 0x1FFu16,

  // Explicit endianness via suffix or mode.
  100u16_le,
  @endian = be,
  42u32,           // big-endian now

  // Non-standard width.
  0x01_02_03u24_be,

  // Strings / bytes.
  b"quux", b'X', c"Hello, world!",

  // Alignment to next multiple of 8 (pads with 0x00)
  align(8),

  // A labeled block and offset expressions.
  start('payload): u16_le,
  'payload: {
    12u16,
    b"PAY",
  },
  end('payload): u16_le,
  len('payload): u16_le,

  // Simple & compound arrays.
  [ 0xFF; 4 ],
  [{ 0xAA, 0xBB }; 2],
);
assert!(data.len() > 0);

Contributing

TBD.

License

This project is dual-licensed under either the MIT or Apache 2.0 license, at your option.

See LICENSE-MIT for the MIT license text.
See LICENSE-APACHE for the Apache 2.0 license text.

You may use this project under the terms of either license.

Acknowledgements