# Ware

Immutable and mutable middleware chains.

Ware allows you to create middleware chains that pass through and modify a value
as they go along. You can imagine a middleware chain as something like this:

```rust
let initial_value = 1;

fn middleware_1(value: i32) -> i32 {
	value + 1
}

fn middleware_2(value: i32) -> i32 {
	value * 5
}

let result = middleware_2(middleware_1(initial_value));
assert_eq!(result, 10);
```

## Mutable middleware

The default is middleware that has free access to mutate the value that's being passed
through, thanks to `RefCell`:

```rust
use ware::Ware;
use std::ops::{Add, Mul};

let mut middleware_chain: Ware<i32> = Ware::new();

middleware_chain.wrap(Box::new(|mut num| {
	*num = num.add(1);
}));
middleware_chain.wrap(Box::new(|mut num| {
	*num = num.mul(5);
}));

let result = middleware_chain.run(1);
assert_eq!(result, 10);
```

These middleware functions have to return a `()` unit struct, so the best
choice is to leave out a return statement.

Remember to always dereference the argument in a middleware function when directly reassigning,
because otherwise you're destroying the `RefCell`.

## Immutable middleware

If you instead want to rely on immutability, replace `ware::Ware` with `ware::im::Ware`:

```rust
use ware::im::Ware;

let mut middleware_chain: Ware<i32> = Ware::new();

middleware_chain.wrap(Box::new(|num| num + 1));
middleware_chain.wrap(Box::new(|num| num * 5));

let result = middleware_chain.run(1);
assert_eq!(result, 10);
```

Functions that get registered as middleware cannot directly modify their
variables, as they have be of the `Fn` trait. I would
recommend using immutable data structures that are efficient when duplicating values.

Generally, I'd recommend immutable `Ware` when you're working with simple data or when
immutability is absolutely critical to you. However, when you're working with more
complex data structures such as a `HashMap`, that provides its own modification tools,
you might want to opt for the mutable `Ware` instead. You cannot do both, either use the
mutable or the immutable variety.

## Documentation

The documentation is available at https://docs.rs/ware.

## License

Ware is licensed under the AGPL 3.0.