How to default-initialize a struct containing an array in Rust?

Question

What is the recommended way to declare a struct that contains an array, and then create a zero-initialized instance?

Here is the struct:

#[derive(De         


        

Answer 1

I'm afraid you can't do this, you will need to implement Default for your structure yourself:

struct Histogram {
    sum: u32,
    bins: [u32; 256],
}

impl Default for Histogram {
    #[inline]
    fn default() -> Histogram {
        Histogram {
            sum: 0,
            bins: [0; 256],
        }
    }
}

Numeric types have nothing to do with this case, it's more like problems with fixed-size arrays. They still need generic numerical literals to support this kind of things natively.