Hey all, getting to know Rust in my spare time and loving it!

I was working on Project Euler problem 8 in Rust. I thought I had come up with a neat one-liner:

```
fn main()
{
let digits = &[7, 3, 1, 6, 7, 1, 7, 6, 5, 3, 1, 3, 3, 0, 6];
let max = digits.windows(13).map(|win| win.product()).max().unwrap();
println!("{}", max);
}
```

It hits a compiler error, though:

```
main.rs:4:48: 4:57 error: type `&[_]` does not implement any method in scope named `product`
main.rs:4 let max = digits.windows(13).map(|win| win.product()).max().unwrap();
^~~~~~~~~
error: aborting due to previous error
```

Here is how I modified the call to compile correctly:

```
fn main()
{
let digits = &[7, 3, 1, 6, 7, 1, 7, 6, 5, 3, 1, 3, 3, 0, 6];
let max = digits.windows(13).map(|win|
win.iter().fold(1, |a, b| a * b)).max().unwrap();
println!("{}", max);
}
```

How do I give the compiler the right type hints?

Thanks

Chris