for_reddit

Hello.

If i compile this code,

    extern crate noise;
    extern crate rand;

    use noise::*;

    fn test(){
        let mut v = vec![ Brownian2::new( perlin2::<f64>, 4) ];
        println!( "{:?}", v );
    }

 rustc says that v have elemetns with type

     noise::Brownian2<f64, fn(&noise::PermutationTable, &[f64; 2]) -> f64 {noise::perlin2::<f64>}>

Question.
How should i define my type, so following code will compile correctly:
    extern crate noise;
    extern crate rand;

    use noise::*;

    type Generator = <... there is something to be ...>;

    fn test() {
        let mut a: Vec<Generator> = Vec::new();
        a.push( Brownian2::new( &perlin2::<f64>, 4) );
    }