# Genfut

This is a tool to generate a Rust library to interact with exported functions from a Futhark file.

## Usage

### As an executable binary
```shell
genfut <Rust lib name> <futhark_file.fut>
```

### Note that use of `bindings` module may not be generally portable. Use with caution.

### As a library

`build.rs`
```rust
use genfut::{genfut, Opt};

fn main() {
    genfut(Opt {
        name: "matmul".to_string(),
        file: std::path::PathBuf::from("matmul.fut"),
        author: "Name <name@example.com>".to_string(),
        version: "0.1.0".to_string(),
        license: "YOLO".to_string(),
        description: "Futhark matrix multiplication example".to_string(),
    })
}
```

### Example on how to use a library generated with genfut

```rust
use matmul::{Array_i32_2d, Error, FutharkContext};

fn main() -> Result<(), Error> {
    let a = vec![1, 2, 3, 4];
    let b = vec![2, 3, 4, 1];

    let mut ctx = FutharkContext::new()?;

    let a_arr = Array_i32_2d::from_vec(ctx, &a, &vec![2, 2])?;
    let b_arr = Array_i32_2d::from_vec(ctx, &b, &vec![2, 2])?;

    let res_arr = ctx.matmul(a_arr, b_arr)?;

    let res = &res_arr.to_vec()?;

    for i in 0..4 {
        print!("{} ", res.0[i]);
        if i == 1 {
            print!("\n");
        }
    }
    print!("\n");
    println!("{:?}", res.0);
    Ok(())
}
```
### MacOS

For the time being, due to quirks of the total toolchain, MacOS is unsupported. Generated libraries will build on MacOS
and do not require that OpenCL be installed. However, calling any of the API functions at runtime may result in an
error, so users of that library should avoid doing so on MacOS.