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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-07 05:48:48 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-07 05:48:48 +0000
commitef24de24a82fe681581cc130f342363c47c0969a (patch)
tree0d494f7e1a38b95c92426f58fe6eaa877303a86c /vendor/itertools/src/either_or_both.rs
parentReleasing progress-linux version 1.74.1+dfsg1-1~progress7.99u1. (diff)
downloadrustc-ef24de24a82fe681581cc130f342363c47c0969a.tar.xz
rustc-ef24de24a82fe681581cc130f342363c47c0969a.zip
Merging upstream version 1.75.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/itertools/src/either_or_both.rs')
-rw-r--r--vendor/itertools/src/either_or_both.rs259
1 files changed, 250 insertions, 9 deletions
diff --git a/vendor/itertools/src/either_or_both.rs b/vendor/itertools/src/either_or_both.rs
index ef3985f75..cf65fe788 100644
--- a/vendor/itertools/src/either_or_both.rs
+++ b/vendor/itertools/src/either_or_both.rs
@@ -1,3 +1,5 @@
+use core::ops::{Deref, DerefMut};
+
use crate::EitherOrBoth::*;
use either::Either;
@@ -14,7 +16,7 @@ pub enum EitherOrBoth<A, B> {
}
impl<A, B> EitherOrBoth<A, B> {
- /// If `Left`, or `Both`, return true, otherwise, return false.
+ /// If `Left`, or `Both`, return true. Otherwise, return false.
pub fn has_left(&self) -> bool {
self.as_ref().left().is_some()
}
@@ -24,7 +26,7 @@ impl<A, B> EitherOrBoth<A, B> {
self.as_ref().right().is_some()
}
- /// If Left, return true otherwise, return false.
+ /// If `Left`, return true. Otherwise, return false.
/// Exclusive version of [`has_left`](EitherOrBoth::has_left).
pub fn is_left(&self) -> bool {
match *self {
@@ -33,7 +35,7 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
- /// If Right, return true otherwise, return false.
+ /// If `Right`, return true. Otherwise, return false.
/// Exclusive version of [`has_right`](EitherOrBoth::has_right).
pub fn is_right(&self) -> bool {
match *self {
@@ -42,13 +44,12 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
- /// If Right, return true otherwise, return false.
- /// Equivalent to `self.as_ref().both().is_some()`.
+ /// 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`.
+ /// 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),
@@ -56,7 +57,7 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
- /// If `Right`, or `Both`, return `Some` with the right value, otherwise, return `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),
@@ -64,7 +65,57 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
- /// If Both, return `Some` tuple containing left and right.
+ /// 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)),
@@ -72,6 +123,28 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
+ /// 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 {
@@ -90,6 +163,32 @@ impl<A, B> EitherOrBoth<A, B> {
}
}
+ /// 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 {
@@ -227,10 +326,152 @@ impl<A, B> EitherOrBoth<A, B> {
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 the product of `f` applied where `Both` are present.
+ /// 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.
+ ///
+ /// # 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);
+ /// ```
pub fn reduce<F>(self, f: F) -> T
where
F: FnOnce(T, T) -> T,