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use std::fmt;
use std::ops::Deref;
use crate::monoid::{Monoid, Sum};
pub trait Measured: Clone {
type Measure: Monoid + Clone;
fn measure(&self) -> Self::Measure;
}
#[derive(Clone, PartialEq, Eq)]
pub struct Size<T>(pub T);
impl<T> fmt::Debug for Size<T>
where
T: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
self.0.fmt(f)
}
}
impl<T> Measured for Size<T>
where
T: Clone,
{
type Measure = Sum<usize>;
fn measure(&self) -> Self::Measure {
Sum(1)
}
}
impl<T> Deref for Size<T> {
type Target = T;
fn deref(&self) -> &Self::Target {
&self.0
}
}