radn-rs/src/flow/speculative.rs
2023-06-18 11:43:26 +00:00

113 lines
4.0 KiB
Rust

use fail::*;
use crate::func::*;
type Frwa<'a, A, E0, E1, Fallible> =
Wrap<'a, Result<WrapE<'a, A, E0, Fallible>, E1>, <Fallible as MonadFailAny<'a>>::T>;
type Wwa<'a, A, E0, E1, Fallible> = WrapE<'a, WrapE<'a, A, E0, Fallible>, E1, Fallible>;
trait SpeculativeFailImpl<'a>: MonadFailAny<'a> {
fn _speculative_a_wb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
a: A,
wb: WrapE<'a, B, E0, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
Self::map_err(<Self::W<E0> as Functor>::fmap(wb, |b| (a, b)), Ok)
}
fn _speculative_ra_wb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
ra: Result<A, E0>,
wb: WrapE<'a, B, E0, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
match ra {
Ok(a) => Self::_speculative_a_wb(a, wb),
Err(e0) => Self::fail(Ok(e0)),
}
}
fn _speculative_ra_rwb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
ra: Result<A, E0>,
rwb: Result<WrapE<'a, B, E0, Self>, E1>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
match rwb {
Ok(wb) => Self::_speculative_ra_wb(ra, wb),
Err(e1) => Self::fail(Err(e1)),
}
}
fn _speculative_ra_frwb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
ra: Result<A, E0>,
frwb: Frwa<'a, B, E0, E1, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
Self::stuff(<Self::T as Monad>::bind(frwb, |rwb| {
Self::unstuff(Self::_speculative_ra_rwb(ra, rwb))
}))
}
fn _speculative_fra_wb<A: 'a, B: 'a, E0: 'a>(
fra: Wrap<'a, Result<A, E0>, Self::T>,
wb: WrapE<'a, B, E0, Self>,
) -> WrapE<'a, (A, B), E0, Self> {
<Self::W<E0> as ApplicativeTuple>::tuple((Self::stuff(fra), wb))
}
fn _speculative_wa_frwb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
wa: WrapE<'a, A, E0, Self>,
frwb: Frwa<'a, B, E0, E1, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
Self::stuff(<<Self as MonadFailAny>::T as Monad>::join(
<<Self as MonadFailAny>::T as Functor>::fmap(
Self::T::select_map(Self::unstuff(wa), frwb, |selected| match selected {
Selected::A(ra, frwb) => Self::_speculative_ra_frwb(ra, frwb),
Selected::B(fra, Ok(wb)) => {
Self::map_err(Self::_speculative_fra_wb(fra, wb), Ok)
}
Selected::B(_, Err(e1)) => Self::fail(Err(e1)),
}),
Self::unstuff,
),
))
}
fn _speculative_frwa_wb<A: 'a, B: 'a, E0: 'a, E1: 'a>(
frwa: Frwa<'a, A, E0, E1, Self>,
wb: WrapE<'a, B, E0, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
<Self::W<Result<E0, E1>> as Functor>::fmap(
Self::_speculative_wa_frwb(wb, frwa),
|(b, a)| (a, b),
)
}
fn _speculative<A: 'a, B: 'a, E0: 'a, E1: 'a>(
wwa: Wwa<'a, A, E0, E1, Self>,
wwb: Wwa<'a, B, E0, E1, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
Self::stuff(<Self::T as Monad>::join(<Self::T as Functor>::fmap(
Self::T::select_map(
Self::unstuff(wwa),
Self::unstuff(wwb),
|selected| match selected {
Selected::A(Ok(wa), frwb) => Self::_speculative_wa_frwb(wa, frwb),
Selected::A(Err(e1), _) => Self::fail(Err(e1)),
Selected::B(frwa, Ok(wb)) => Self::_speculative_frwa_wb(frwa, wb),
Selected::B(_, Err(e1)) => Self::fail(Err(e1)),
},
),
Self::unstuff,
)))
}
}
pub trait SpeculativeFail<'a>: MonadFailAny<'a> {
fn speculative<A: 'a, B: 'a, E0: 'a, E1: 'a>(
wwa: Wwa<'a, A, E0, E1, Self>,
wwb: Wwa<'a, B, E0, E1, Self>,
) -> WrapE<'a, (A, B), Result<E0, E1>, Self> {
Self::_speculative(wwa, wwb)
}
}
impl<'a, Fallible: ?Sized + MonadFailAny<'a>> SpeculativeFailImpl<'a> for Fallible {}
impl<'a, Fallible: ?Sized + MonadFailAny<'a>> SpeculativeFail<'a> for Fallible {}