summaryrefslogtreecommitdiffstats
path: root/vendor/itertools-0.10.5/src/either_or_both.rs
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/itertools-0.10.5/src/either_or_both.rs')
-rw-r--r--vendor/itertools-0.10.5/src/either_or_both.rs254
1 files changed, 254 insertions, 0 deletions
diff --git a/vendor/itertools-0.10.5/src/either_or_both.rs b/vendor/itertools-0.10.5/src/either_or_both.rs
new file mode 100644
index 000000000..ef3985f75
--- /dev/null
+++ b/vendor/itertools-0.10.5/src/either_or_both.rs
@@ -0,0 +1,254 @@
+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> {
+ /// 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 {
+ match *self {
+ Left(_) => true,
+ _ => false,
+ }
+ }
+
+ /// If Right, return true otherwise, return false.
+ /// Exclusive version of [`has_right`](EitherOrBoth::has_right).
+ pub fn is_right(&self) -> bool {
+ match *self {
+ Right(_) => true,
+ _ => false,
+ }
+ }
+
+ /// If Right, return true otherwise, return false.
+ /// Equivalent to `self.as_ref().both().is_some()`.
+ 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,
+ }
+ }
+
+ /// If Both, return `Some` tuple containing left and right.
+ pub fn both(self) -> Option<(A, B)> {
+ match self {
+ Both(a, b) => Some((a, b)),
+ _ => None,
+ }
+ }
+
+ /// 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),
+ }
+ }
+
+ /// 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 {
+ EitherOrBoth::Left(l) => (l, B::default()),
+ EitherOrBoth::Right(r) => (A::default(), r),
+ EitherOrBoth::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),
+ }
+ }
+}
+
+impl<T> EitherOrBoth<T, T> {
+ /// Return either value of left, right, or the product of `f` applied where `Both` are present.
+ 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,
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-09-10 04:58:39 +0000