use std::any::{Any, TypeId};
use std::collections::HashMap;
pub struct TypeMap {
data: HashMap<TypeId, Box<Any>>
}
impl TypeMap {
pub fn new() -> TypeMap {
TypeMap { data: HashMap::new() }
}
pub fn find<T: Any>(&self) -> Option<&T> {
self.data.get(&TypeId::of::<T>()).and_then(|a| a.downcast_ref())
}
pub fn find_mut<T: Any>(&mut self) -> Option<&mut T> {
self.data.get_mut(&TypeId::of::<T>()).and_then(|a| a.downcast_mut())
}
pub fn insert<T: Any>(&mut self, val: T) -> bool {
self.data.insert(TypeId::of::<T>(), Box::new(val) as Box<Any>).is_none()
}
pub fn remove<T: Any>(&mut self) -> bool {
self.data.remove(&TypeId::of::<T>()).is_some()
}
pub fn contains<T: Any>(&self) -> bool {
self.data.contains_key(&TypeId::of::<T>())
}
pub fn pop<T: Any>(&mut self) -> Option<T> {
let data = match self.data.remove(&TypeId::of::<T>()) {
Some(data) => data,
None => return None,
};
Some(*data.downcast::<T>().ok().unwrap())
}
}
#[cfg(test)]
mod tests {
use super::TypeMap;
#[test]
fn smoke() {
let mut m = TypeMap::new();
assert!(m.insert(1));
assert_eq!(*m.find::<i32>().unwrap(), 1);
assert_eq!(*m.find_mut::<i32>().unwrap(), 1);
assert!(!m.insert(2));
assert!(m.remove::<i32>());
assert!(!m.contains::<i32>());
assert!(m.insert(4));
assert_eq!(m.pop::<i32>().unwrap(), 4);
}
}