Module ext 

The two BEVE extensions that carry data, as ordinary Rust types.

BEVE’s core covers what JSON covers. Its extensions cover what scientific data needs on top of that: Complex for a complex number, and Matrix for an array that knows its own shape. Both are stored compactly, which is the point of them. A run of complex numbers is one header, one count, and the interleaved components, so a Vec<Complex<f64>> is a single memcpy in each direction, exactly as a Vec<f64> is.

use structio::{Complex, Matrix, MatrixLayout};

let signal = vec![Complex::new(1.0f64, 2.0), Complex::new(3.0, -4.0)];
let bytes = structio::to_beve(&signal);
assert_eq!(structio::from_beve::<Vec<Complex<f64>>>(&bytes).unwrap(), signal);

let m = Matrix::new(MatrixLayout::RowMajor, vec![2, 3], (0..6).collect()).unwrap();
let bytes = structio::to_beve(&m);
assert_eq!(structio::from_beve::<Matrix<i32>>(&bytes).unwrap(), m);

They are types, not a numeric library

Complex has two public fields and no arithmetic. It is here so a complex number can be stored, and it is deliberately not a competitor to num-complex: nothing here would make it a better one, and adding operators would make this crate a numerics dependency for everyone who only wanted to read a file. A program that computes with complex numbers should keep doing so in whatever type it already uses and convert at the edge, which for a #[repr(C)] pair is a field-by-field move the optimizer removes.

Both formats, one type

object! declares a struct for JSON and BEVE at once, so a field of either type has to work in both. Where BEVE has an extension, JSON gets the encoding it would have had anyway: a complex number is [re, im] and a matrix is {"layout":…,"extents":[…],"value":[…]}. Those are the forms beve_to_json writes as well, and the forms both types still read back from BEVE, so a producer that has no extensions is understood without a second declaration.

What is not here

The other two extensions carry no data of their own. The delimiter separates documents in a stream and is handled by beve::Documents, being no value at all; where a value belongs it is refused. The type tag is deprecated, and is still stepped over correctly wherever it appears.

Structs

Complex

A complex number: two components of the same type, real part first.

Matrix

An owned matrix: a layout, the length of each dimension, and the elements in that order.

MatrixRef

A borrowed matrix, for writing one whose data you already hold.

Enums

MatrixLayout

Which index of a matrix varies fastest in storage.