radn-rs/src/func/classes/soloclass.rs

72 lines
1.5 KiB
Rust

use crate::func::*;
pub struct SoloClass;
impl WeakFunctor for SoloClass {
type F<'a, A> = A;
}
impl Functor for SoloClass {
fn fmap<'a, A: 'a, B: 'a, F: 'a + FnOnce(A) -> B>(f: F, fa: Self::F<'a, A>) -> Self::F<'a, B> {
f(fa)
}
fn replace<'a, A: 'a, B: 'a>(fa: Self::F<'a, A>, b: B) -> Self::F<'a, B> {
drop(fa);
b
}
fn void<'a, A: 'a>(fa: Self::F<'a, A>) -> Self::F<'a, ()> {
drop(fa);
}
}
impl ApplicativeSeq for SoloClass {
fn seq<'a, A: 'a, B: 'a, F: 'a + FnOnce(A) -> B>(
ff: Self::F<'a, F>,
fa: Self::F<'a, A>,
) -> Self::F<'a, B> {
ff(fa)
}
}
impl ApplicativeLA2 for SoloClass {
fn la2<'a, A: 'a, B: 'a, C: 'a, F: 'a + FnOnce(A, B) -> C>(
f: F,
fa: Self::F<'a, A>,
fb: Self::F<'a, B>,
) -> Self::F<'a, C> {
f(fa, fb)
}
}
impl Applicative for SoloClass {
fn pure<'a, A: 'a>(a: A) -> Self::F<'a, A> {
a
}
fn discard_first<'a, A: 'a, B: 'a>(fa: Self::F<'a, A>, fb: Self::F<'a, B>) -> Self::F<'a, B> {
drop(fa);
fb
}
fn discard_second<'a, A: 'a, B: 'a>(fa: Self::F<'a, A>, fb: Self::F<'a, B>) -> Self::F<'a, A> {
drop(fb);
fa
}
}
impl Monad for SoloClass {
fn bind<'a, A: 'a, B: 'a, F: 'a + FnOnce(A) -> Self::F<'a, B>>(
fa: Self::F<'a, A>,
f: F,
) -> Self::F<'a, B> {
f(fa)
}
fn join<'a, A: 'a>(ffa: Self::F<'a, Self::F<'a, A>>) -> Self::F<'a, A>
{
ffa
}
}