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Diffstat (limited to 'vendor/itertools/src/either_or_both.rs')
| -rw-r--r-- | vendor/itertools/src/either_or_both.rs | 514 |
1 files changed, 0 insertions, 514 deletions
diff --git a/vendor/itertools/src/either_or_both.rs b/vendor/itertools/src/either_or_both.rs deleted file mode 100644 index b7a7fc14..00000000 --- a/vendor/itertools/src/either_or_both.rs +++ /dev/null @@ -1,514 +0,0 @@ -use core::ops::{Deref, DerefMut}; - -use crate::EitherOrBoth::*; - -use either::Either; - -/// Value that either holds a single A or B, or both. -#[derive(Clone, PartialEq, Eq, Hash, Debug)] -pub enum EitherOrBoth<A, B = A> { - /// Both values are present. - Both(A, B), - /// Only the left value of type `A` is present. - Left(A), - /// Only the right value of type `B` is present. - Right(B), -} - -impl<A, B> EitherOrBoth<A, B> { - /// If `Left`, or `Both`, return true. Otherwise, return false. - pub fn has_left(&self) -> bool { - self.as_ref().left().is_some() - } - - /// If `Right`, or `Both`, return true, otherwise, return false. - pub fn has_right(&self) -> bool { - self.as_ref().right().is_some() - } - - /// If `Left`, return true. Otherwise, return false. - /// Exclusive version of [`has_left`](EitherOrBoth::has_left). - pub fn is_left(&self) -> bool { - matches!(self, Left(_)) - } - - /// If `Right`, return true. Otherwise, return false. - /// Exclusive version of [`has_right`](EitherOrBoth::has_right). - pub fn is_right(&self) -> bool { - matches!(self, Right(_)) - } - - /// If `Both`, return true. Otherwise, return false. - pub fn is_both(&self) -> bool { - self.as_ref().both().is_some() - } - - /// If `Left`, or `Both`, return `Some` with the left value. Otherwise, return `None`. - pub fn left(self) -> Option<A> { - match self { - Left(left) | Both(left, _) => Some(left), - _ => None, - } - } - - /// If `Right`, or `Both`, return `Some` with the right value. Otherwise, return `None`. - pub fn right(self) -> Option<B> { - match self { - Right(right) | Both(_, right) => Some(right), - _ => None, - } - } - - /// Return tuple of options corresponding to the left and right value respectively - /// - /// If `Left` return `(Some(..), None)`, if `Right` return `(None,Some(..))`, else return - /// `(Some(..),Some(..))` - pub fn left_and_right(self) -> (Option<A>, Option<B>) { - self.map_any(Some, Some).or_default() - } - - /// If `Left`, return `Some` with the left value. If `Right` or `Both`, return `None`. - /// - /// # Examples - /// - /// ``` - /// // On the `Left` variant. - /// # use itertools::{EitherOrBoth, EitherOrBoth::{Left, Right, Both}}; - /// let x: EitherOrBoth<_, ()> = Left("bonjour"); - /// assert_eq!(x.just_left(), Some("bonjour")); - /// - /// // On the `Right` variant. - /// let x: EitherOrBoth<(), _> = Right("hola"); - /// assert_eq!(x.just_left(), None); - /// - /// // On the `Both` variant. - /// let x = Both("bonjour", "hola"); - /// assert_eq!(x.just_left(), None); - /// ``` - pub fn just_left(self) -> Option<A> { - match self { - Left(left) => Some(left), - _ => None, - } - } - - /// If `Right`, return `Some` with the right value. If `Left` or `Both`, return `None`. - /// - /// # Examples - /// - /// ``` - /// // On the `Left` variant. - /// # use itertools::{EitherOrBoth::{Left, Right, Both}, EitherOrBoth}; - /// let x: EitherOrBoth<_, ()> = Left("auf wiedersehen"); - /// assert_eq!(x.just_left(), Some("auf wiedersehen")); - /// - /// // On the `Right` variant. - /// let x: EitherOrBoth<(), _> = Right("adios"); - /// assert_eq!(x.just_left(), None); - /// - /// // On the `Both` variant. - /// let x = Both("auf wiedersehen", "adios"); - /// assert_eq!(x.just_left(), None); - /// ``` - pub fn just_right(self) -> Option<B> { - match self { - Right(right) => Some(right), - _ => None, - } - } - - /// If `Both`, return `Some` containing the left and right values. Otherwise, return `None`. - pub fn both(self) -> Option<(A, B)> { - match self { - Both(a, b) => Some((a, b)), - _ => None, - } - } - - /// If `Left` or `Both`, return the left value. Otherwise, convert the right value and return it. - pub fn into_left(self) -> A - where - B: Into<A>, - { - match self { - Left(a) | Both(a, _) => a, - Right(b) => b.into(), - } - } - - /// If `Right` or `Both`, return the right value. Otherwise, convert the left value and return it. - pub fn into_right(self) -> B - where - A: Into<B>, - { - match self { - Right(b) | Both(_, b) => b, - Left(a) => a.into(), - } - } - - /// Converts from `&EitherOrBoth<A, B>` to `EitherOrBoth<&A, &B>`. - 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), - } - } - - /// Converts from `&mut EitherOrBoth<A, B>` to `EitherOrBoth<&mut A, &mut B>`. - 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), - } - } - - /// Converts from `&EitherOrBoth<A, B>` to `EitherOrBoth<&_, &_>` using the [`Deref`] trait. - pub fn as_deref(&self) -> EitherOrBoth<&A::Target, &B::Target> - where - A: Deref, - B: Deref, - { - match *self { - Left(ref left) => Left(left), - Right(ref right) => Right(right), - Both(ref left, ref right) => Both(left, right), - } - } - - /// Converts from `&mut EitherOrBoth<A, B>` to `EitherOrBoth<&mut _, &mut _>` using the [`DerefMut`] trait. - pub fn as_deref_mut(&mut self) -> EitherOrBoth<&mut A::Target, &mut B::Target> - where - A: DerefMut, - B: DerefMut, - { - match *self { - Left(ref mut left) => Left(left), - Right(ref mut right) => Right(right), - Both(ref mut left, ref mut right) => Both(left, right), - } - } - - /// Convert `EitherOrBoth<A, B>` to `EitherOrBoth<B, A>`. - pub fn flip(self) -> EitherOrBoth<B, A> { - match self { - Left(a) => Right(a), - Right(b) => Left(b), - Both(a, b) => Both(b, a), - } - } - - /// Apply the function `f` on the value `a` in `Left(a)` or `Both(a, b)` variants. If it is - /// present rewrapping the result in `self`'s original variant. - 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), - } - } - - /// Apply the function `f` on the value `b` in `Right(b)` or `Both(a, b)` variants. - /// If it is present rewrapping the result in `self`'s original variant. - 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)), - } - } - - /// Apply the functions `f` and `g` on the value `a` and `b` respectively; - /// found in `Left(a)`, `Right(b)`, or `Both(a, b)` variants. - /// The Result is rewrapped `self`'s original variant. - 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)), - } - } - - /// Apply the function `f` on the value `a` in `Left(a)` or `Both(a, _)` variants if it is - /// present. - 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), - } - } - - /// Apply the function `f` on the value `b` - /// in `Right(b)` or `Both(_, b)` variants if it is present. - 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), - } - } - - /// Returns a tuple consisting of the `l` and `r` in `Both(l, r)`, if present. - /// Otherwise, returns the wrapped value for the present element, and the supplied - /// value for the other. The first (`l`) argument is used for a missing `Left` - /// value. The second (`r`) argument is used for a missing `Right` value. - /// - /// Arguments passed to `or` are eagerly evaluated; if you are passing - /// the result of a function call, it is recommended to use [`or_else`], - /// which is lazily evaluated. - /// - /// [`or_else`]: EitherOrBoth::or_else - /// - /// # Examples - /// - /// ``` - /// # use itertools::EitherOrBoth; - /// assert_eq!(EitherOrBoth::Both("tree", 1).or("stone", 5), ("tree", 1)); - /// assert_eq!(EitherOrBoth::Left("tree").or("stone", 5), ("tree", 5)); - /// assert_eq!(EitherOrBoth::Right(1).or("stone", 5), ("stone", 1)); - /// ``` - pub fn or(self, l: A, r: B) -> (A, B) { - match self { - Left(inner_l) => (inner_l, r), - Right(inner_r) => (l, inner_r), - Both(inner_l, inner_r) => (inner_l, inner_r), - } - } - - /// Returns a tuple consisting of the `l` and `r` in `Both(l, r)`, if present. - /// Otherwise, returns the wrapped value for the present element, and the [`default`](Default::default) - /// for the other. - pub fn or_default(self) -> (A, B) - where - A: Default, - B: Default, - { - match self { - Left(l) => (l, B::default()), - Right(r) => (A::default(), r), - Both(l, r) => (l, r), - } - } - - /// Returns a tuple consisting of the `l` and `r` in `Both(l, r)`, if present. - /// Otherwise, returns the wrapped value for the present element, and computes the - /// missing value with the supplied closure. The first argument (`l`) is used for a - /// missing `Left` value. The second argument (`r`) is used for a missing `Right` value. - /// - /// # Examples - /// - /// ``` - /// # use itertools::EitherOrBoth; - /// let k = 10; - /// assert_eq!(EitherOrBoth::Both("tree", 1).or_else(|| "stone", || 2 * k), ("tree", 1)); - /// assert_eq!(EitherOrBoth::Left("tree").or_else(|| "stone", || 2 * k), ("tree", 20)); - /// assert_eq!(EitherOrBoth::Right(1).or_else(|| "stone", || 2 * k), ("stone", 1)); - /// ``` - pub fn or_else<L: FnOnce() -> A, R: FnOnce() -> B>(self, l: L, r: R) -> (A, B) { - match self { - Left(inner_l) => (inner_l, r()), - Right(inner_r) => (l(), inner_r), - Both(inner_l, inner_r) => (inner_l, inner_r), - } - } - - /// Returns a mutable reference to the left value. If the left value is not present, - /// it is replaced with `val`. - pub fn left_or_insert(&mut self, val: A) -> &mut A { - self.left_or_insert_with(|| val) - } - - /// Returns a mutable reference to the right value. If the right value is not present, - /// it is replaced with `val`. - pub fn right_or_insert(&mut self, val: B) -> &mut B { - self.right_or_insert_with(|| val) - } - - /// If the left value is not present, replace it the value computed by the closure `f`. - /// Returns a mutable reference to the now-present left value. - pub fn left_or_insert_with<F>(&mut self, f: F) -> &mut A - where - F: FnOnce() -> A, - { - match self { - Left(left) | Both(left, _) => left, - Right(_) => self.insert_left(f()), - } - } - - /// If the right value is not present, replace it the value computed by the closure `f`. - /// Returns a mutable reference to the now-present right value. - pub fn right_or_insert_with<F>(&mut self, f: F) -> &mut B - where - F: FnOnce() -> B, - { - match self { - Right(right) | Both(_, right) => right, - Left(_) => self.insert_right(f()), - } - } - - /// Sets the `left` value of this instance, and returns a mutable reference to it. - /// Does not affect the `right` value. - /// - /// # Examples - /// ``` - /// # use itertools::{EitherOrBoth, EitherOrBoth::{Left, Right, Both}}; - /// - /// // Overwriting a pre-existing value. - /// let mut either: EitherOrBoth<_, ()> = Left(0_u32); - /// assert_eq!(*either.insert_left(69), 69); - /// - /// // Inserting a second value. - /// let mut either = Right("no"); - /// assert_eq!(*either.insert_left("yes"), "yes"); - /// assert_eq!(either, Both("yes", "no")); - /// ``` - pub fn insert_left(&mut self, val: A) -> &mut A { - match self { - Left(left) | Both(left, _) => { - *left = val; - left - } - Right(right) => { - // This is like a map in place operation. We move out of the reference, - // change the value, and then move back into the reference. - unsafe { - // SAFETY: We know this pointer is valid for reading since we got it from a reference. - let right = std::ptr::read(right as *mut _); - // SAFETY: Again, we know the pointer is valid since we got it from a reference. - std::ptr::write(self as *mut _, Both(val, right)); - } - - if let Both(left, _) = self { - left - } else { - // SAFETY: The above pattern will always match, since we just - // set `self` equal to `Both`. - unsafe { std::hint::unreachable_unchecked() } - } - } - } - } - - /// Sets the `right` value of this instance, and returns a mutable reference to it. - /// Does not affect the `left` value. - /// - /// # Examples - /// ``` - /// # use itertools::{EitherOrBoth, EitherOrBoth::{Left, Both}}; - /// // Overwriting a pre-existing value. - /// let mut either: EitherOrBoth<_, ()> = Left(0_u32); - /// assert_eq!(*either.insert_left(69), 69); - /// - /// // Inserting a second value. - /// let mut either = Left("what's"); - /// assert_eq!(*either.insert_right(9 + 10), 21 - 2); - /// assert_eq!(either, Both("what's", 9+10)); - /// ``` - pub fn insert_right(&mut self, val: B) -> &mut B { - match self { - Right(right) | Both(_, right) => { - *right = val; - right - } - Left(left) => { - // This is like a map in place operation. We move out of the reference, - // change the value, and then move back into the reference. - unsafe { - // SAFETY: We know this pointer is valid for reading since we got it from a reference. - let left = std::ptr::read(left as *mut _); - // SAFETY: Again, we know the pointer is valid since we got it from a reference. - std::ptr::write(self as *mut _, Both(left, val)); - } - if let Both(_, right) = self { - right - } else { - // SAFETY: The above pattern will always match, since we just - // set `self` equal to `Both`. - unsafe { std::hint::unreachable_unchecked() } - } - } - } - } - - /// Set `self` to `Both(..)`, containing the specified left and right values, - /// and returns a mutable reference to those values. - pub fn insert_both(&mut self, left: A, right: B) -> (&mut A, &mut B) { - *self = Both(left, right); - if let Both(left, right) = self { - (left, right) - } else { - // SAFETY: The above pattern will always match, since we just - // set `self` equal to `Both`. - unsafe { std::hint::unreachable_unchecked() } - } - } -} - -impl<T> EitherOrBoth<T, T> { - /// Return either value of left, right, or apply a function `f` to both values if both are present. - /// The input function has to return the same type as both Right and Left carry. - /// - /// This function can be used to preferrably extract the left resp. right value, - /// but fall back to the other (i.e. right resp. left) if the preferred one is not present. - /// - /// # Examples - /// ``` - /// # use itertools::EitherOrBoth; - /// assert_eq!(EitherOrBoth::Both(3, 7).reduce(u32::max), 7); - /// assert_eq!(EitherOrBoth::Left(3).reduce(u32::max), 3); - /// assert_eq!(EitherOrBoth::Right(7).reduce(u32::max), 7); - /// - /// // Extract the left value if present, fall back to the right otherwise. - /// assert_eq!(EitherOrBoth::Left("left").reduce(|l, _r| l), "left"); - /// assert_eq!(EitherOrBoth::Right("right").reduce(|l, _r| l), "right"); - /// assert_eq!(EitherOrBoth::Both("left", "right").reduce(|l, _r| l), "left"); - /// ``` - 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> From<EitherOrBoth<A, B>> for Option<Either<A, B>> { - fn from(value: EitherOrBoth<A, B>) -> Self { - match value { - Left(l) => Some(Either::Left(l)), - Right(r) => Some(Either::Right(r)), - Both(..) => None, - } - } -} - -impl<A, B> From<Either<A, B>> for EitherOrBoth<A, B> { - fn from(either: Either<A, B>) -> Self { - match either { - Either::Left(l) => Left(l), - Either::Right(l) => Right(l), - } - } -} |
