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use crate::EitherOrBoth::*;
use either::Either;
#[derive(Clone, PartialEq, Eq, Hash, Debug)]
pub enum EitherOrBoth<A, B> {
Both(A, B),
Left(A),
Right(B),
}
impl<A, B> EitherOrBoth<A, B> {
pub fn has_left(&self) -> bool {
self.as_ref().left().is_some()
}
pub fn has_right(&self) -> bool {
self.as_ref().right().is_some()
}
pub fn is_left(&self) -> bool {
match *self {
Left(_) => true,
_ => false,
}
}
pub fn is_right(&self) -> bool {
match *self {
Right(_) => true,
_ => false,
}
}
pub fn is_both(&self) -> bool {
self.as_ref().both().is_some()
}
pub fn left(self) -> Option<A> {
match self {
Left(left) | Both(left, _) => Some(left),
_ => None,
}
}
pub fn right(self) -> Option<B> {
match self {
Right(right) | Both(_, right) => Some(right),
_ => None,
}
}
pub fn both(self) -> Option<(A, B)> {
match self {
Both(a, b) => Some((a, b)),
_ => None,
}
}
pub fn as_ref(&self) -> EitherOrBoth<&A, &B> {
match *self {
Left(ref left) => Left(left),
Right(ref right) => Right(right),
Both(ref left, ref right) => Both(left, right),
}
}
pub fn as_mut(&mut self) -> EitherOrBoth<&mut A, &mut B> {
match *self {
Left(ref mut left) => Left(left),
Right(ref mut right) => Right(right),
Both(ref mut left, ref mut right) => Both(left, right),
}
}
pub fn flip(self) -> EitherOrBoth<B, A> {
match self {
Left(a) => Right(a),
Right(b) => Left(b),
Both(a, b) => Both(b, a),
}
}
pub fn map_left<F, M>(self, f: F) -> EitherOrBoth<M, B>
where
F: FnOnce(A) -> M,
{
match self {
Both(a, b) => Both(f(a), b),
Left(a) => Left(f(a)),
Right(b) => Right(b),
}
}
pub fn map_right<F, M>(self, f: F) -> EitherOrBoth<A, M>
where
F: FnOnce(B) -> M,
{
match self {
Left(a) => Left(a),
Right(b) => Right(f(b)),
Both(a, b) => Both(a, f(b)),
}
}
pub fn map_any<F, L, G, R>(self, f: F, g: G) -> EitherOrBoth<L, R>
where
F: FnOnce(A) -> L,
G: FnOnce(B) -> R,
{
match self {
Left(a) => Left(f(a)),
Right(b) => Right(g(b)),
Both(a, b) => Both(f(a), g(b)),
}
}
pub fn left_and_then<F, L>(self, f: F) -> EitherOrBoth<L, B>
where
F: FnOnce(A) -> EitherOrBoth<L, B>,
{
match self {
Left(a) | Both(a, _) => f(a),
Right(b) => Right(b),
}
}
pub fn right_and_then<F, R>(self, f: F) -> EitherOrBoth<A, R>
where
F: FnOnce(B) -> EitherOrBoth<A, R>,
{
match self {
Left(a) => Left(a),
Right(b) | Both(_, b) => f(b),
}
}
pub fn or_default(self) -> (A, B)
where
A: Default,
B: Default,
{
match self {
EitherOrBoth::Left(l) => (l, B::default()),
EitherOrBoth::Right(r) => (A::default(), r),
EitherOrBoth::Both(l, r) => (l, r),
}
}
}
impl<T> EitherOrBoth<T, T> {
pub fn reduce<F>(self, f: F) -> T
where
F: FnOnce(T, T) -> T,
{
match self {
Left(a) => a,
Right(b) => b,
Both(a, b) => f(a, b),
}
}
}
impl<A, B> Into<Option<Either<A, B>>> for EitherOrBoth<A, B> {
fn into(self) -> Option<Either<A, B>> {
match self {
EitherOrBoth::Left(l) => Some(Either::Left(l)),
EitherOrBoth::Right(r) => Some(Either::Right(r)),
_ => None,
}
}
}