1 use rand::distributions::{Distribution, Standard}; 2 use rand::prelude::*; 3 use rand::rngs::StdRng; 4 vec<T>(size: usize, start: usize) -> Option<Vec<T>> where Standard: Distribution<T>,5pub fn vec<T>(size: usize, start: usize) -> Option<Vec<T>> 6 where 7 Standard: Distribution<T>, 8 { 9 if size > start + 2 { 10 let mut rng = StdRng::from_entropy(); 11 12 Some((0..size).map(|_| rng.gen()).collect()) 13 } else { 14 None 15 } 16 } 17