bad-optics/src/lenses/identity.rs

26 lines
443 B
Rust

use crate::{
lenses::{LensOver, LensView},
OpticsTrait,
};
#[allow(non_camel_case_types)]
#[derive(Clone, Copy)]
pub struct id;
impl OpticsTrait for id {}
impl<T> LensView<T> for id {
type Field = T;
fn view(&self, thing: T) -> Self::Field {
thing
}
}
impl<T> LensOver<T> for id {
fn over<F>(&self, thing: T, f: F) -> T
where
F: FnOnce(Self::Field) -> Self::Field,
{
f(thing)
}
}