simple_endian_derive 0.4.10

Proc-macros for the simple_endian crate.
Documentation 
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# `simple_endian_derive`

This crate provides the proc-macro implementation behind `#[derive(Endianize)]` for the [`simple_endian`](https://crates.io/crates/simple_endian) crate.

You generally **should not** depend on this crate directly.
Enable the `derive` feature on `simple_endian` instead, which re-exports the derive macro.

## Usage

In your `Cargo.toml`:

```toml
[dependencies]
simple_endian = { version = "0.4", features = ["derive"] }
```

Then:

```rust
use simple_endian::Endianize;

#[derive(Endianize)]
#[endian(le)]
#[repr(C)]
struct Header {
    magic: u32,
    version: u16,
}

// Generated by the macro:
// - `HeaderWire` (wire-format representation)
```

## What gets generated

For a type named `T`, the macro generates a `TWire` companion type whose fields are endian-aware and whose layout is intended for IO.

The recommended workflow in the `simple_endian` ecosystem is **native-first**:

* Use the native types in your application logic.
* Convert at boundaries by reading/writing `TWire` (or using `read_native` / `write_native` when `io-std` is enabled).

## Supported helper attributes

### Container-level

* `#[endian(le)]` / `#[endian(be)]` (required)
* `#[wire_repr(...)]` – controls the generated wire type representation (e.g. `#[repr(C)]`, `#[repr(C, packed)]`)
* `#[wire_derive(...)]` – derives to apply to the generated `*Wire` type
* `#[wire_default]` / `#[wire_default(...)]` – controls `Default` generation for wire types

### Field-level

* `#[text(...)]` – fixed-size text fields (feature-gated by `simple_endian` text features)
* `#[tuple_text]` – support for tuple enum variants in text contexts

## Important limitation: enum wire derives

Enum wire types are represented as `tag + union payload` to match on-wire layout.
Unions cannot derive many common traits (notably `Debug`, `PartialEq`, `Eq`, `Hash`, ...).

If you apply `#[wire_derive(...)]` to an enum, keep those restrictions in mind.
In most cases you should keep derives on the native enum (where they make semantic sense), and convert at IO boundaries.

## Repository / contributing

This crate is maintained in the `simple-endian-rs` repository alongside the main library crate.