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This is the simplest and the fastest (faster than [`Vec`](https://doc.rust-lang.org/std/vec/struct.Vec.html)!) implementation of a 
last-in-first-out [stack data structure](https://en.wikipedia.org/wiki/Stack_%28abstract_data_type%29), 
on [stack](https://en.wikipedia.org/wiki/Call_stack), 
when stack elements are `Copy` implementing primitives. 
This is basically a wrapper around an [uninitialized](https://doc.rust-lang.org/nomicon/uninitialized.html) array.
When it is created on stack, its elements contain no specific data.
Then, when you `push_unchecked(x)`, the head of the stack is moved forward
and `x` is placed into the element of the array. When you `pop_unchecked()`,
the head is moved backward and the data is retrieved from the array.
There are no boundary checks, that's why both `push_unchecked()` and `pop_unchecked()` may lead to undefined
behavior. Use `push()` and `pop()`, which are safer, but slower.
For even slower but even safer behavior, you can use `try_push()` and `try_pop()`.

First, add this to `Cargo.toml`:

```toml
[dependencies]
microstack = "0.0.5"
```

Then, use it like this (mind the `unsafe` blocks, they give the fastest performance, 
but [undefined behavior](https://doc.rust-lang.org/reference/behavior-considered-undefined.html) 
if you go over the stack boundaries):

```rust
use microstack::Stack;
let mut s : Stack<&str, 10> = Stack::new(); // allocation on stack
unsafe { s.push_unchecked("foo") }; // no boundary checks here
unsafe { s.push_unchecked("bar") }; // and here
assert_eq!("bar", unsafe { s.pop_unchecked() });
assert_eq!(1, s.len());
```

Pay attention, here the stack is created with an extra generic argument `10`. This is 
the total size of the stack data structure, which is allocated on stack when `::new()` is called. 

Read [the API documentation](https://docs.rs/microstack/latest/microstack/).

## How to Contribute

First, install [Rust](https://www.rust-lang.org/tools/install) and then:

```bash
$ cargo test -vv
```

If everything goes well, fork repository, make changes, send us a [pull request](https://www.yegor256.com/2014/04/15/github-guidelines.html).
We will review your changes and apply them to the `master` branch shortly,
provided they don't violate our quality standards. To avoid frustration,
before sending us your pull request please run `cargo test` again. Also, 
run `cargo fmt` and `cargo clippy`.

Also, before you start making changes, run benchmarks:

```bash
$ rustup run nightly cargo bench
```

Then, after the changes you make, run it again. Compare the results. If your changes
degrade performance, think twice before submitting a pull request.