# rust-bfi
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Simple and fast Brainfuck interpreter perfectly suited for machine learning needs.

## Example
```rust
extern crate bfi;

use bfi::{BfMachine, b};

let code = b("+++[->,.<]");  // `b` converts an `&str` to a byte vector: `pub fn b(s: &str) -> Vec<u8>`
let input = b("jackdaws love my big sphinx of quartz");
let mut output = Vec::new();

let mut machine = BfMachine::new();
let res = machine.exec(&code, &input, &mut output);

assert_eq!(output, b("jackdaws"));
assert_eq!(res, Ok(code.len()));
```

## Docs
[Here](https://docs.rs/bfi) they are.


## Implementation details
* The memory tape is infinitely long to the right.
* Going to the left of the starting cell causes an `Err(BfError::Memory)`.
* Cells can hold values from 0 to 255.
* Addition and subtraction over- and underflow silently.
* End of input results in an early return.

## Why another Brainfuck interpreter?
I like idea of Brainfuck as an environment for reinforcement learning. After
searching crates, I haven't found anything decent for interpreting BF in
runtime, so I wrote this little thing.