See [RFC as Readme-For-Crate](https://github.com/oooutlk/structx/blob/main/README.md)
for more.

# Overview

This project provides simulation of anonymous struct and named arguments in
Rust, using proc macros `structx!{}`, `Structx!{}`, `#[named_args]` and
`args!{}`.

## Usage of this crate

Add the following in your Cargo.toml file:

```toml
[dependencies]
structx = "0.1"

[build-dependencies]
inwelling = "0.5"

[package.metadata.inwelling]
structx = true
```

Add the following in your build.rs file:

```rust
inwelling::to( "structx" );
```

Add the following in your .rs files:

```rust
use structx::*;
```

If you want to use named arguments, add the following:

```rust
use structx::named_args::*;
```

# Definitions and notations of anonymous structs

Anonymous structs are `struct`s without the needs of providing struct names.
However, the field names are mandatory. Anonymous structs are of the same type
if and only if they are composed of the same set of field names. The order of
fields are irrelevant.

## Value of anonymous structs

The notation of an anonymous struct's value is `structx!{}`.

## Examples of anonymous struct's values

```rust
let foo = structx!{ i: 3, b: true };
let bar = structx!{ x, y };
```

## Type of anonymous structs

The notation of an anonymous struct's type is `Structx!{}`.

## Examples of anonymous struct's types

```rust
fn foo( x: i32, y: i32 ) -> Structx!{ x: i32, y: i32 } {
    structx!{ x, y: y+1 }
}
```

## Traits derived for anonymous structs

Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord, Hash.

```rust
let a = structx!{ width :  800, height: 600 };
let b = structx!{ height:  600, width : 800 };
let c = structx!{ width : 1024, height: 768 };
assert_eq!( a, b );
assert_ne!( a, c );
```

# Simulation of named arguments

At definition site, add attributes `#[named_args]` to functions.

```rust
#[named_args]
fn set_size( width: u32, height: u32 ) { todo!() }
```

At call site, wrap arguments with `args!{}`.

```rust
set_size( args!{ width: 1024, height: 768 });
```

# License

Under Apache License 2.0 or MIT License, at your will.