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extern crate crypto;
extern crate num;
extern crate rand;
extern crate chrono;
pub mod bt;
pub mod contiguous;
pub mod convert;
pub mod net;
pub mod send;
pub mod sha;
pub mod test;
pub mod trans;
pub mod error;
use std::mem;
pub fn fisher_shuffle<T: Default>(list: &mut [T]) {
for i in 0..list.len() {
let swap_index = (rand::random::<usize>() % (list.len() - i)) + i;
let src_val = mem::replace(&mut list[i], T::default());
let dst_val = mem::replace(&mut list[swap_index], T::default());
list[i] = dst_val;
list[swap_index] = src_val;
}
}
#[cfg(test)]
mod tests {
#[test]
fn positive_fisher_shuffle() {
let mut test_slice = [1, 2, 3, 4];
super::fisher_shuffle(&mut test_slice);
assert!(test_slice.contains(&1));
assert!(test_slice.contains(&2));
assert!(test_slice.contains(&3));
assert!(test_slice.contains(&4));
}
}