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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 00:47:55 +0000 |
commit | 26a029d407be480d791972afb5975cf62c9360a6 (patch) | |
tree | f435a8308119effd964b339f76abb83a57c29483 /third_party/rust/futures-util/src/fns.rs | |
parent | Initial commit. (diff) | |
download | firefox-26a029d407be480d791972afb5975cf62c9360a6.tar.xz firefox-26a029d407be480d791972afb5975cf62c9360a6.zip |
Adding upstream version 124.0.1.upstream/124.0.1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/futures-util/src/fns.rs')
-rw-r--r-- | third_party/rust/futures-util/src/fns.rs | 372 |
1 files changed, 372 insertions, 0 deletions
diff --git a/third_party/rust/futures-util/src/fns.rs b/third_party/rust/futures-util/src/fns.rs new file mode 100644 index 0000000000..37ee03e6df --- /dev/null +++ b/third_party/rust/futures-util/src/fns.rs @@ -0,0 +1,372 @@ +use core::fmt::{self, Debug}; +use core::marker::PhantomData; + +pub trait FnOnce1<A> { + type Output; + fn call_once(self, arg: A) -> Self::Output; +} + +impl<T, A, R> FnOnce1<A> for T +where + T: FnOnce(A) -> R, +{ + type Output = R; + fn call_once(self, arg: A) -> R { + self(arg) + } +} + +pub trait FnMut1<A>: FnOnce1<A> { + fn call_mut(&mut self, arg: A) -> Self::Output; +} + +impl<T, A, R> FnMut1<A> for T +where + T: FnMut(A) -> R, +{ + fn call_mut(&mut self, arg: A) -> R { + self(arg) + } +} + +// Not used, but present for completeness +#[allow(unreachable_pub)] +pub trait Fn1<A>: FnMut1<A> { + fn call(&self, arg: A) -> Self::Output; +} + +impl<T, A, R> Fn1<A> for T +where + T: Fn(A) -> R, +{ + fn call(&self, arg: A) -> R { + self(arg) + } +} + +macro_rules! trivial_fn_impls { + ($name:ident <$($arg:ident),*> $t:ty = $debug:literal) => { + impl<$($arg),*> Copy for $t {} + impl<$($arg),*> Clone for $t { + fn clone(&self) -> Self { *self } + } + impl<$($arg),*> Debug for $t { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.write_str($debug) + } + } + impl<$($arg,)* A> FnMut1<A> for $t where Self: FnOnce1<A> { + fn call_mut(&mut self, arg: A) -> Self::Output { + self.call_once(arg) + } + } + impl<$($arg,)* A> Fn1<A> for $t where Self: FnOnce1<A> { + fn call(&self, arg: A) -> Self::Output { + self.call_once(arg) + } + } + pub(crate) fn $name<$($arg),*>() -> $t { + Default::default() + } + } +} + +pub struct OkFn<E>(PhantomData<fn(E)>); + +impl<E> Default for OkFn<E> { + fn default() -> Self { + Self(PhantomData) + } +} + +impl<A, E> FnOnce1<A> for OkFn<E> { + type Output = Result<A, E>; + fn call_once(self, arg: A) -> Self::Output { + Ok(arg) + } +} + +trivial_fn_impls!(ok_fn <T> OkFn<T> = "Ok"); + +#[derive(Debug, Copy, Clone, Default)] +pub struct ChainFn<F, G>(F, G); + +impl<F, G, A> FnOnce1<A> for ChainFn<F, G> +where + F: FnOnce1<A>, + G: FnOnce1<F::Output>, +{ + type Output = G::Output; + fn call_once(self, arg: A) -> Self::Output { + self.1.call_once(self.0.call_once(arg)) + } +} +impl<F, G, A> FnMut1<A> for ChainFn<F, G> +where + F: FnMut1<A>, + G: FnMut1<F::Output>, +{ + fn call_mut(&mut self, arg: A) -> Self::Output { + self.1.call_mut(self.0.call_mut(arg)) + } +} +impl<F, G, A> Fn1<A> for ChainFn<F, G> +where + F: Fn1<A>, + G: Fn1<F::Output>, +{ + fn call(&self, arg: A) -> Self::Output { + self.1.call(self.0.call(arg)) + } +} +pub(crate) fn chain_fn<F, G>(f: F, g: G) -> ChainFn<F, G> { + ChainFn(f, g) +} + +#[derive(Default)] +pub struct MergeResultFn; + +impl<T> FnOnce1<Result<T, T>> for MergeResultFn { + type Output = T; + fn call_once(self, arg: Result<T, T>) -> Self::Output { + match arg { + Ok(x) => x, + Err(x) => x, + } + } +} +trivial_fn_impls!(merge_result_fn <> MergeResultFn = "merge_result"); + +#[derive(Debug, Copy, Clone, Default)] +pub struct InspectFn<F>(F); + +#[allow(single_use_lifetimes)] // https://github.com/rust-lang/rust/issues/55058 +impl<F, A> FnOnce1<A> for InspectFn<F> +where + F: for<'a> FnOnce1<&'a A, Output = ()>, +{ + type Output = A; + fn call_once(self, arg: A) -> Self::Output { + self.0.call_once(&arg); + arg + } +} +#[allow(single_use_lifetimes)] // https://github.com/rust-lang/rust/issues/55058 +impl<F, A> FnMut1<A> for InspectFn<F> +where + F: for<'a> FnMut1<&'a A, Output = ()>, +{ + fn call_mut(&mut self, arg: A) -> Self::Output { + self.0.call_mut(&arg); + arg + } +} +#[allow(single_use_lifetimes)] // https://github.com/rust-lang/rust/issues/55058 +impl<F, A> Fn1<A> for InspectFn<F> +where + F: for<'a> Fn1<&'a A, Output = ()>, +{ + fn call(&self, arg: A) -> Self::Output { + self.0.call(&arg); + arg + } +} +pub(crate) fn inspect_fn<F>(f: F) -> InspectFn<F> { + InspectFn(f) +} + +#[derive(Debug, Copy, Clone, Default)] +pub struct MapOkFn<F>(F); + +impl<F, T, E> FnOnce1<Result<T, E>> for MapOkFn<F> +where + F: FnOnce1<T>, +{ + type Output = Result<F::Output, E>; + fn call_once(self, arg: Result<T, E>) -> Self::Output { + arg.map(|x| self.0.call_once(x)) + } +} +impl<F, T, E> FnMut1<Result<T, E>> for MapOkFn<F> +where + F: FnMut1<T>, +{ + fn call_mut(&mut self, arg: Result<T, E>) -> Self::Output { + arg.map(|x| self.0.call_mut(x)) + } +} +impl<F, T, E> Fn1<Result<T, E>> for MapOkFn<F> +where + F: Fn1<T>, +{ + fn call(&self, arg: Result<T, E>) -> Self::Output { + arg.map(|x| self.0.call(x)) + } +} +pub(crate) fn map_ok_fn<F>(f: F) -> MapOkFn<F> { + MapOkFn(f) +} + +#[derive(Debug, Copy, Clone, Default)] +pub struct MapErrFn<F>(F); + +impl<F, T, E> FnOnce1<Result<T, E>> for MapErrFn<F> +where + F: FnOnce1<E>, +{ + type Output = Result<T, F::Output>; + fn call_once(self, arg: Result<T, E>) -> Self::Output { + arg.map_err(|x| self.0.call_once(x)) + } +} +impl<F, T, E> FnMut1<Result<T, E>> for MapErrFn<F> +where + F: FnMut1<E>, +{ + fn call_mut(&mut self, arg: Result<T, E>) -> Self::Output { + arg.map_err(|x| self.0.call_mut(x)) + } +} +impl<F, T, E> Fn1<Result<T, E>> for MapErrFn<F> +where + F: Fn1<E>, +{ + fn call(&self, arg: Result<T, E>) -> Self::Output { + arg.map_err(|x| self.0.call(x)) + } +} +pub(crate) fn map_err_fn<F>(f: F) -> MapErrFn<F> { + MapErrFn(f) +} + +#[derive(Debug, Copy, Clone)] +pub struct InspectOkFn<F>(F); + +impl<'a, F, T, E> FnOnce1<&'a Result<T, E>> for InspectOkFn<F> +where + F: FnOnce1<&'a T, Output = ()>, +{ + type Output = (); + fn call_once(self, arg: &'a Result<T, E>) -> Self::Output { + if let Ok(x) = arg { + self.0.call_once(x) + } + } +} +impl<'a, F, T, E> FnMut1<&'a Result<T, E>> for InspectOkFn<F> +where + F: FnMut1<&'a T, Output = ()>, +{ + fn call_mut(&mut self, arg: &'a Result<T, E>) -> Self::Output { + if let Ok(x) = arg { + self.0.call_mut(x) + } + } +} +impl<'a, F, T, E> Fn1<&'a Result<T, E>> for InspectOkFn<F> +where + F: Fn1<&'a T, Output = ()>, +{ + fn call(&self, arg: &'a Result<T, E>) -> Self::Output { + if let Ok(x) = arg { + self.0.call(x) + } + } +} +pub(crate) fn inspect_ok_fn<F>(f: F) -> InspectOkFn<F> { + InspectOkFn(f) +} + +#[derive(Debug, Copy, Clone)] +pub struct InspectErrFn<F>(F); + +impl<'a, F, T, E> FnOnce1<&'a Result<T, E>> for InspectErrFn<F> +where + F: FnOnce1<&'a E, Output = ()>, +{ + type Output = (); + fn call_once(self, arg: &'a Result<T, E>) -> Self::Output { + if let Err(x) = arg { + self.0.call_once(x) + } + } +} +impl<'a, F, T, E> FnMut1<&'a Result<T, E>> for InspectErrFn<F> +where + F: FnMut1<&'a E, Output = ()>, +{ + fn call_mut(&mut self, arg: &'a Result<T, E>) -> Self::Output { + if let Err(x) = arg { + self.0.call_mut(x) + } + } +} +impl<'a, F, T, E> Fn1<&'a Result<T, E>> for InspectErrFn<F> +where + F: Fn1<&'a E, Output = ()>, +{ + fn call(&self, arg: &'a Result<T, E>) -> Self::Output { + if let Err(x) = arg { + self.0.call(x) + } + } +} +pub(crate) fn inspect_err_fn<F>(f: F) -> InspectErrFn<F> { + InspectErrFn(f) +} + +pub(crate) type MapOkOrElseFn<F, G> = ChainFn<MapOkFn<F>, ChainFn<MapErrFn<G>, MergeResultFn>>; +pub(crate) fn map_ok_or_else_fn<F, G>(f: F, g: G) -> MapOkOrElseFn<F, G> { + chain_fn(map_ok_fn(f), chain_fn(map_err_fn(g), merge_result_fn())) +} + +#[derive(Debug, Copy, Clone, Default)] +pub struct UnwrapOrElseFn<F>(F); + +impl<F, T, E> FnOnce1<Result<T, E>> for UnwrapOrElseFn<F> +where + F: FnOnce1<E, Output = T>, +{ + type Output = T; + fn call_once(self, arg: Result<T, E>) -> Self::Output { + arg.unwrap_or_else(|x| self.0.call_once(x)) + } +} +impl<F, T, E> FnMut1<Result<T, E>> for UnwrapOrElseFn<F> +where + F: FnMut1<E, Output = T>, +{ + fn call_mut(&mut self, arg: Result<T, E>) -> Self::Output { + arg.unwrap_or_else(|x| self.0.call_mut(x)) + } +} +impl<F, T, E> Fn1<Result<T, E>> for UnwrapOrElseFn<F> +where + F: Fn1<E, Output = T>, +{ + fn call(&self, arg: Result<T, E>) -> Self::Output { + arg.unwrap_or_else(|x| self.0.call(x)) + } +} +pub(crate) fn unwrap_or_else_fn<F>(f: F) -> UnwrapOrElseFn<F> { + UnwrapOrElseFn(f) +} + +pub struct IntoFn<T>(PhantomData<fn() -> T>); + +impl<T> Default for IntoFn<T> { + fn default() -> Self { + Self(PhantomData) + } +} +impl<A, T> FnOnce1<A> for IntoFn<T> +where + A: Into<T>, +{ + type Output = T; + fn call_once(self, arg: A) -> Self::Output { + arg.into() + } +} + +trivial_fn_impls!(into_fn <T> IntoFn<T> = "Into::into"); |