use {Type, Error};
use std::collections::{HashMap, BTreeMap};
use std::hash::Hash;
use std::io::prelude::*;
pub type SizeType = u32;
macro_rules! impl_map_type {
( $ty:ident => K: $( $k_pred:ident ),+ ) => {
impl<K, V> Type for $ty<K, V>
where K: Type + $( $k_pred +)+,
V: Type
{
fn read(read: &mut Read) -> Result<Self, Error> {
let mut map = $ty::new();
let length = SizeType::read(read)?;
for _ in 0..length {
let key = K::read(read)?;
let value = V::read(read)?;
map.insert(key, value);
}
Ok(map)
}
fn write(&self, write: &mut Write) -> Result<(), Error> {
(self.len() as SizeType).write(write)?;
for (key, value) in self.iter() {
key.write(write)?;
value.write(write)?;
}
Ok(())
}
}
}
}
impl_map_type!(HashMap => K: Hash, Eq);
impl_map_type!(BTreeMap => K: Ord);