nom-derive 0.2.0

Custom derive nom parsers from struct
Documentation 
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# nom-derive

[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](./LICENSE-MIT)
[![Apache License 2.0](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](./LICENSE-APACHE)
[![Build Status](https://travis-ci.org/chifflier/nom-derive.svg?branch=master)](https://travis-ci.org/chifflier/nom-derive)

## Overview

nom-derive is a custom derive attribute, to derive [nom] parsers automatically from the structure definition.

- [API documentation](https://docs.rs/nom-derive)

*This is only test code for now. Feedback welcome !*

## `#[derive(Nom)]`

This crate exposes a single custom-derive macro `Nom` which
implements `parse` for the struct it is applied to.

The goal of this project is that:

* `derive(Nom)` should be enough for you to derive [nom] parsers for simple
  structures easily, without having to write it manually
* it allows overriding any parsing method by your own
* it allows using generated parsing functions along with handwritten parsers and
  combining them without efforts

## Usage

Add to your `Cargo.toml` file::

```
 nom-derive = "0.2"
 nom = "4.2"
```

Add `#[derive(Nom)]` to the structure(s) you want.

See the [tests](https://github.com/rust-bakery/nom-derive/tree/master/tests)
directory for examples.

## Example

This implementation:

```rust
#[macro_use]
extern crate nom_derive;

#[macro_use]
extern crate nom;

use nom::*;

#[derive(Nom)]
struct SimpleStruct {
    pub a: u32,
    b: u64,
}
```

Allows you to generate the [nom] parser for `SimpleStruct` automatically. The function is called `SimpleStruct::parse`.

The generated code is equivalent to::

```rust
impl SimpleStruct {
    fn parse(i: &[u8]) -> IResult<&[u8],SimpleStruct> {
        do_parse!(
            i,
            a: be_u32 >>
            b: be_u64 >>
            ( SimpleStruct{ a,b } )
        )
    }
}
```

[nom]: https://github.com/geal/nom

## Limitations

* Debugging macros is hard. Debugging macros generated by a custom derive is a
  nightmare. The [expand](https://github.com/dtolnay/cargo-expand) cargo
  subcommand can help !

## License

Licensed under either of

 * Apache License, Version 2.0
   ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
 * MIT license
   ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)

at your option.

## Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.