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Diffstat (limited to 'src/libcore/ops/range.rs')
| -rw-r--r-- | src/libcore/ops/range.rs | 885 |
1 files changed, 0 insertions, 885 deletions
diff --git a/src/libcore/ops/range.rs b/src/libcore/ops/range.rs deleted file mode 100644 index 179038d1977..00000000000 --- a/src/libcore/ops/range.rs +++ /dev/null @@ -1,885 +0,0 @@ -use crate::fmt; -use crate::hash::Hash; - -/// An unbounded range (`..`). -/// -/// `RangeFull` is primarily used as a [slicing index], its shorthand is `..`. -/// It cannot serve as an [`Iterator`] because it doesn't have a starting point. -/// -/// # Examples -/// -/// The `..` syntax is a `RangeFull`: -/// -/// ``` -/// assert_eq!((..), std::ops::RangeFull); -/// ``` -/// -/// It does not have an [`IntoIterator`] implementation, so you can't use it in -/// a `for` loop directly. This won't compile: -/// -/// ```compile_fail,E0277 -/// for i in .. { -/// // ... -/// } -/// ``` -/// -/// Used as a [slicing index], `RangeFull` produces the full array as a slice. -/// -/// ``` -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); // RangeFull -/// assert_eq!(arr[ .. 3], [0,1,2 ]); -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); -/// assert_eq!(arr[1.. 3], [ 1,2 ]); -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); -/// ``` -/// -/// [`IntoIterator`]: ../iter/trait.Iterator.html -/// [`Iterator`]: ../iter/trait.IntoIterator.html -/// [slicing index]: ../slice/trait.SliceIndex.html -#[doc(alias = "..")] -#[derive(Copy, Clone, Default, PartialEq, Eq, Hash)] -#[stable(feature = "rust1", since = "1.0.0")] -pub struct RangeFull; - -#[stable(feature = "rust1", since = "1.0.0")] -impl fmt::Debug for RangeFull { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(fmt, "..") - } -} - -/// A (half-open) range bounded inclusively below and exclusively above -/// (`start..end`). -/// -/// The `Range` `start..end` contains all values with `x >= start` and -/// `x < end`. It is empty unless `start < end`. -/// -/// # Examples -/// -/// ``` -/// assert_eq!((3..5), std::ops::Range { start: 3, end: 5 }); -/// assert_eq!(3 + 4 + 5, (3..6).sum()); -/// -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); -/// assert_eq!(arr[ .. 3], [0,1,2 ]); -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); -/// assert_eq!(arr[1.. 3], [ 1,2 ]); // Range -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); -/// ``` -#[doc(alias = "..")] -#[derive(Clone, Default, PartialEq, Eq, Hash)] // not Copy -- see #27186 -#[stable(feature = "rust1", since = "1.0.0")] -pub struct Range<Idx> { - /// The lower bound of the range (inclusive). - #[stable(feature = "rust1", since = "1.0.0")] - pub start: Idx, - /// The upper bound of the range (exclusive). - #[stable(feature = "rust1", since = "1.0.0")] - pub end: Idx, -} - -#[stable(feature = "rust1", since = "1.0.0")] -impl<Idx: fmt::Debug> fmt::Debug for Range<Idx> { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - self.start.fmt(fmt)?; - write!(fmt, "..")?; - self.end.fmt(fmt)?; - Ok(()) - } -} - -impl<Idx: PartialOrd<Idx>> Range<Idx> { - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!(!(3..5).contains(&2)); - /// assert!( (3..5).contains(&3)); - /// assert!( (3..5).contains(&4)); - /// assert!(!(3..5).contains(&5)); - /// - /// assert!(!(3..3).contains(&3)); - /// assert!(!(3..2).contains(&3)); - /// - /// assert!( (0.0..1.0).contains(&0.5)); - /// assert!(!(0.0..1.0).contains(&f32::NAN)); - /// assert!(!(0.0..f32::NAN).contains(&0.5)); - /// assert!(!(f32::NAN..1.0).contains(&0.5)); - /// ``` - #[stable(feature = "range_contains", since = "1.35.0")] - pub fn contains<U>(&self, item: &U) -> bool - where - Idx: PartialOrd<U>, - U: ?Sized + PartialOrd<Idx>, - { - <Self as RangeBounds<Idx>>::contains(self, item) - } - - /// Returns `true` if the range contains no items. - /// - /// # Examples - /// - /// ``` - /// #![feature(range_is_empty)] - /// - /// assert!(!(3..5).is_empty()); - /// assert!( (3..3).is_empty()); - /// assert!( (3..2).is_empty()); - /// ``` - /// - /// The range is empty if either side is incomparable: - /// - /// ``` - /// #![feature(range_is_empty)] - /// - /// assert!(!(3.0..5.0).is_empty()); - /// assert!( (3.0..f32::NAN).is_empty()); - /// assert!( (f32::NAN..5.0).is_empty()); - /// ``` - #[unstable(feature = "range_is_empty", reason = "recently added", issue = "48111")] - pub fn is_empty(&self) -> bool { - !(self.start < self.end) - } -} - -/// A range only bounded inclusively below (`start..`). -/// -/// The `RangeFrom` `start..` contains all values with `x >= start`. -/// -/// *Note*: Overflow in the [`Iterator`] implementation (when the contained -/// data type reaches its numerical limit) is allowed to panic, wrap, or -/// saturate. This behavior is defined by the implementation of the [`Step`] -/// trait. For primitive integers, this follows the normal rules, and respects -/// the overflow checks profile (panic in debug, wrap in release). Note also -/// that overflow happens earlier than you might assume: the overflow happens -/// in the call to `next` that yields the maximum value, as the range must be -/// set to a state to yield the next value. -/// -/// [`Step`]: crate::iter::Step -/// -/// # Examples -/// -/// ``` -/// assert_eq!((2..), std::ops::RangeFrom { start: 2 }); -/// assert_eq!(2 + 3 + 4, (2..).take(3).sum()); -/// -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); -/// assert_eq!(arr[ .. 3], [0,1,2 ]); -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); // RangeFrom -/// assert_eq!(arr[1.. 3], [ 1,2 ]); -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); -/// ``` -/// -/// [`Iterator`]: ../iter/trait.IntoIterator.html -#[doc(alias = "..")] -#[derive(Clone, PartialEq, Eq, Hash)] // not Copy -- see #27186 -#[stable(feature = "rust1", since = "1.0.0")] -pub struct RangeFrom<Idx> { - /// The lower bound of the range (inclusive). - #[stable(feature = "rust1", since = "1.0.0")] - pub start: Idx, -} - -#[stable(feature = "rust1", since = "1.0.0")] -impl<Idx: fmt::Debug> fmt::Debug for RangeFrom<Idx> { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - self.start.fmt(fmt)?; - write!(fmt, "..")?; - Ok(()) - } -} - -impl<Idx: PartialOrd<Idx>> RangeFrom<Idx> { - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!(!(3..).contains(&2)); - /// assert!( (3..).contains(&3)); - /// assert!( (3..).contains(&1_000_000_000)); - /// - /// assert!( (0.0..).contains(&0.5)); - /// assert!(!(0.0..).contains(&f32::NAN)); - /// assert!(!(f32::NAN..).contains(&0.5)); - /// ``` - #[stable(feature = "range_contains", since = "1.35.0")] - pub fn contains<U>(&self, item: &U) -> bool - where - Idx: PartialOrd<U>, - U: ?Sized + PartialOrd<Idx>, - { - <Self as RangeBounds<Idx>>::contains(self, item) - } -} - -/// A range only bounded exclusively above (`..end`). -/// -/// The `RangeTo` `..end` contains all values with `x < end`. -/// It cannot serve as an [`Iterator`] because it doesn't have a starting point. -/// -/// # Examples -/// -/// The `..end` syntax is a `RangeTo`: -/// -/// ``` -/// assert_eq!((..5), std::ops::RangeTo { end: 5 }); -/// ``` -/// -/// It does not have an [`IntoIterator`] implementation, so you can't use it in -/// a `for` loop directly. This won't compile: -/// -/// ```compile_fail,E0277 -/// // error[E0277]: the trait bound `std::ops::RangeTo<{integer}>: -/// // std::iter::Iterator` is not satisfied -/// for i in ..5 { -/// // ... -/// } -/// ``` -/// -/// When used as a [slicing index], `RangeTo` produces a slice of all array -/// elements before the index indicated by `end`. -/// -/// ``` -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); -/// assert_eq!(arr[ .. 3], [0,1,2 ]); // RangeTo -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); -/// assert_eq!(arr[1.. 3], [ 1,2 ]); -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); -/// ``` -/// -/// [`IntoIterator`]: ../iter/trait.Iterator.html -/// [`Iterator`]: ../iter/trait.IntoIterator.html -/// [slicing index]: ../slice/trait.SliceIndex.html -#[doc(alias = "..")] -#[derive(Copy, Clone, PartialEq, Eq, Hash)] -#[stable(feature = "rust1", since = "1.0.0")] -pub struct RangeTo<Idx> { - /// The upper bound of the range (exclusive). - #[stable(feature = "rust1", since = "1.0.0")] - pub end: Idx, -} - -#[stable(feature = "rust1", since = "1.0.0")] -impl<Idx: fmt::Debug> fmt::Debug for RangeTo<Idx> { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(fmt, "..")?; - self.end.fmt(fmt)?; - Ok(()) - } -} - -impl<Idx: PartialOrd<Idx>> RangeTo<Idx> { - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!( (..5).contains(&-1_000_000_000)); - /// assert!( (..5).contains(&4)); - /// assert!(!(..5).contains(&5)); - /// - /// assert!( (..1.0).contains(&0.5)); - /// assert!(!(..1.0).contains(&f32::NAN)); - /// assert!(!(..f32::NAN).contains(&0.5)); - /// ``` - #[stable(feature = "range_contains", since = "1.35.0")] - pub fn contains<U>(&self, item: &U) -> bool - where - Idx: PartialOrd<U>, - U: ?Sized + PartialOrd<Idx>, - { - <Self as RangeBounds<Idx>>::contains(self, item) - } -} - -/// A range bounded inclusively below and above (`start..=end`). -/// -/// The `RangeInclusive` `start..=end` contains all values with `x >= start` -/// and `x <= end`. It is empty unless `start <= end`. -/// -/// This iterator is [fused], but the specific values of `start` and `end` after -/// iteration has finished are **unspecified** other than that [`.is_empty()`] -/// will return `true` once no more values will be produced. -/// -/// [fused]: ../iter/trait.FusedIterator.html -/// [`.is_empty()`]: #method.is_empty -/// -/// # Examples -/// -/// ``` -/// assert_eq!((3..=5), std::ops::RangeInclusive::new(3, 5)); -/// assert_eq!(3 + 4 + 5, (3..=5).sum()); -/// -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); -/// assert_eq!(arr[ .. 3], [0,1,2 ]); -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); -/// assert_eq!(arr[1.. 3], [ 1,2 ]); -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); // RangeInclusive -/// ``` -#[doc(alias = "..=")] -#[derive(Clone, PartialEq, Eq, Hash)] // not Copy -- see #27186 -#[stable(feature = "inclusive_range", since = "1.26.0")] -pub struct RangeInclusive<Idx> { - // Note that the fields here are not public to allow changing the - // representation in the future; in particular, while we could plausibly - // expose start/end, modifying them without changing (future/current) - // private fields may lead to incorrect behavior, so we don't want to - // support that mode. - pub(crate) start: Idx, - pub(crate) end: Idx, - - // This field is: - // - `false` upon construction - // - `false` when iteration has yielded an element and the iterator is not exhausted - // - `true` when iteration has been used to exhaust the iterator - // - // This is required to support PartialEq and Hash without a PartialOrd bound or specialization. - pub(crate) exhausted: bool, -} - -impl<Idx> RangeInclusive<Idx> { - /// Creates a new inclusive range. Equivalent to writing `start..=end`. - /// - /// # Examples - /// - /// ``` - /// use std::ops::RangeInclusive; - /// - /// assert_eq!(3..=5, RangeInclusive::new(3, 5)); - /// ``` - #[stable(feature = "inclusive_range_methods", since = "1.27.0")] - #[inline] - #[rustc_promotable] - #[rustc_const_stable(feature = "const_range_new", since = "1.32.0")] - pub const fn new(start: Idx, end: Idx) -> Self { - Self { start, end, exhausted: false } - } - - /// Returns the lower bound of the range (inclusive). - /// - /// When using an inclusive range for iteration, the values of `start()` and - /// [`end()`] are unspecified after the iteration ended. To determine - /// whether the inclusive range is empty, use the [`is_empty()`] method - /// instead of comparing `start() > end()`. - /// - /// Note: the value returned by this method is unspecified after the range - /// has been iterated to exhaustion. - /// - /// [`end()`]: #method.end - /// [`is_empty()`]: #method.is_empty - /// - /// # Examples - /// - /// ``` - /// assert_eq!((3..=5).start(), &3); - /// ``` - #[stable(feature = "inclusive_range_methods", since = "1.27.0")] - #[rustc_const_stable(feature = "const_inclusive_range_methods", since = "1.32.0")] - #[inline] - pub const fn start(&self) -> &Idx { - &self.start - } - - /// Returns the upper bound of the range (inclusive). - /// - /// When using an inclusive range for iteration, the values of [`start()`] - /// and `end()` are unspecified after the iteration ended. To determine - /// whether the inclusive range is empty, use the [`is_empty()`] method - /// instead of comparing `start() > end()`. - /// - /// Note: the value returned by this method is unspecified after the range - /// has been iterated to exhaustion. - /// - /// [`start()`]: #method.start - /// [`is_empty()`]: #method.is_empty - /// - /// # Examples - /// - /// ``` - /// assert_eq!((3..=5).end(), &5); - /// ``` - #[stable(feature = "inclusive_range_methods", since = "1.27.0")] - #[rustc_const_stable(feature = "const_inclusive_range_methods", since = "1.32.0")] - #[inline] - pub const fn end(&self) -> &Idx { - &self.end - } - - /// Destructures the `RangeInclusive` into (lower bound, upper (inclusive) bound). - /// - /// Note: the value returned by this method is unspecified after the range - /// has been iterated to exhaustion. - /// - /// # Examples - /// - /// ``` - /// assert_eq!((3..=5).into_inner(), (3, 5)); - /// ``` - #[stable(feature = "inclusive_range_methods", since = "1.27.0")] - #[inline] - pub fn into_inner(self) -> (Idx, Idx) { - (self.start, self.end) - } -} - -#[stable(feature = "inclusive_range", since = "1.26.0")] -impl<Idx: fmt::Debug> fmt::Debug for RangeInclusive<Idx> { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - self.start.fmt(fmt)?; - write!(fmt, "..=")?; - self.end.fmt(fmt)?; - if self.exhausted { - write!(fmt, " (exhausted)")?; - } - Ok(()) - } -} - -impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> { - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!(!(3..=5).contains(&2)); - /// assert!( (3..=5).contains(&3)); - /// assert!( (3..=5).contains(&4)); - /// assert!( (3..=5).contains(&5)); - /// assert!(!(3..=5).contains(&6)); - /// - /// assert!( (3..=3).contains(&3)); - /// assert!(!(3..=2).contains(&3)); - /// - /// assert!( (0.0..=1.0).contains(&1.0)); - /// assert!(!(0.0..=1.0).contains(&f32::NAN)); - /// assert!(!(0.0..=f32::NAN).contains(&0.0)); - /// assert!(!(f32::NAN..=1.0).contains(&1.0)); - /// ``` - #[stable(feature = "range_contains", since = "1.35.0")] - pub fn contains<U>(&self, item: &U) -> bool - where - Idx: PartialOrd<U>, - U: ?Sized + PartialOrd<Idx>, - { - <Self as RangeBounds<Idx>>::contains(self, item) - } - - /// Returns `true` if the range contains no items. - /// - /// # Examples - /// - /// ``` - /// #![feature(range_is_empty)] - /// - /// assert!(!(3..=5).is_empty()); - /// assert!(!(3..=3).is_empty()); - /// assert!( (3..=2).is_empty()); - /// ``` - /// - /// The range is empty if either side is incomparable: - /// - /// ``` - /// #![feature(range_is_empty)] - /// - /// assert!(!(3.0..=5.0).is_empty()); - /// assert!( (3.0..=f32::NAN).is_empty()); - /// assert!( (f32::NAN..=5.0).is_empty()); - /// ``` - /// - /// This method returns `true` after iteration has finished: - /// - /// ``` - /// #![feature(range_is_empty)] - /// - /// let mut r = 3..=5; - /// for _ in r.by_ref() {} - /// // Precise field values are unspecified here - /// assert!(r.is_empty()); - /// ``` - #[unstable(feature = "range_is_empty", reason = "recently added", issue = "48111")] - #[inline] - pub fn is_empty(&self) -> bool { - self.exhausted || !(self.start <= self.end) - } -} - -/// A range only bounded inclusively above (`..=end`). -/// -/// The `RangeToInclusive` `..=end` contains all values with `x <= end`. -/// It cannot serve as an [`Iterator`] because it doesn't have a starting point. -/// -/// # Examples -/// -/// The `..=end` syntax is a `RangeToInclusive`: -/// -/// ``` -/// assert_eq!((..=5), std::ops::RangeToInclusive{ end: 5 }); -/// ``` -/// -/// It does not have an [`IntoIterator`] implementation, so you can't use it in a -/// `for` loop directly. This won't compile: -/// -/// ```compile_fail,E0277 -/// // error[E0277]: the trait bound `std::ops::RangeToInclusive<{integer}>: -/// // std::iter::Iterator` is not satisfied -/// for i in ..=5 { -/// // ... -/// } -/// ``` -/// -/// When used as a [slicing index], `RangeToInclusive` produces a slice of all -/// array elements up to and including the index indicated by `end`. -/// -/// ``` -/// let arr = [0, 1, 2, 3, 4]; -/// assert_eq!(arr[ .. ], [0,1,2,3,4]); -/// assert_eq!(arr[ .. 3], [0,1,2 ]); -/// assert_eq!(arr[ ..=3], [0,1,2,3 ]); // RangeToInclusive -/// assert_eq!(arr[1.. ], [ 1,2,3,4]); -/// assert_eq!(arr[1.. 3], [ 1,2 ]); -/// assert_eq!(arr[1..=3], [ 1,2,3 ]); -/// ``` -/// -/// [`IntoIterator`]: ../iter/trait.Iterator.html -/// [`Iterator`]: ../iter/trait.IntoIterator.html -/// [slicing index]: ../slice/trait.SliceIndex.html -#[doc(alias = "..=")] -#[derive(Copy, Clone, PartialEq, Eq, Hash)] -#[stable(feature = "inclusive_range", since = "1.26.0")] -pub struct RangeToInclusive<Idx> { - /// The upper bound of the range (inclusive) - #[stable(feature = "inclusive_range", since = "1.26.0")] - pub end: Idx, -} - -#[stable(feature = "inclusive_range", since = "1.26.0")] -impl<Idx: fmt::Debug> fmt::Debug for RangeToInclusive<Idx> { - fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { - write!(fmt, "..=")?; - self.end.fmt(fmt)?; - Ok(()) - } -} - -impl<Idx: PartialOrd<Idx>> RangeToInclusive<Idx> { - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!( (..=5).contains(&-1_000_000_000)); - /// assert!( (..=5).contains(&5)); - /// assert!(!(..=5).contains(&6)); - /// - /// assert!( (..=1.0).contains(&1.0)); - /// assert!(!(..=1.0).contains(&f32::NAN)); - /// assert!(!(..=f32::NAN).contains(&0.5)); - /// ``` - #[stable(feature = "range_contains", since = "1.35.0")] - pub fn contains<U>(&self, item: &U) -> bool - where - Idx: PartialOrd<U>, - U: ?Sized + PartialOrd<Idx>, - { - <Self as RangeBounds<Idx>>::contains(self, item) - } -} - -// RangeToInclusive<Idx> cannot impl From<RangeTo<Idx>> -// because underflow would be possible with (..0).into() - -/// An endpoint of a range of keys. -/// -/// # Examples -/// -/// `Bound`s are range endpoints: -/// -/// ``` -/// use std::ops::Bound::*; -/// use std::ops::RangeBounds; -/// -/// assert_eq!((..100).start_bound(), Unbounded); -/// assert_eq!((1..12).start_bound(), Included(&1)); -/// assert_eq!((1..12).end_bound(), Excluded(&12)); -/// ``` -/// -/// Using a tuple of `Bound`s as an argument to [`BTreeMap::range`]. -/// Note that in most cases, it's better to use range syntax (`1..5`) instead. -/// -/// ``` -/// use std::collections::BTreeMap; -/// use std::ops::Bound::{Excluded, Included, Unbounded}; -/// -/// let mut map = BTreeMap::new(); -/// map.insert(3, "a"); -/// map.insert(5, "b"); -/// map.insert(8, "c"); -/// -/// for (key, value) in map.range((Excluded(3), Included(8))) { -/// println!("{}: {}", key, value); -/// } -/// -/// assert_eq!(Some((&3, &"a")), map.range((Unbounded, Included(5))).next()); -/// ``` -/// -/// [`BTreeMap::range`]: ../../std/collections/btree_map/struct.BTreeMap.html#method.range -#[stable(feature = "collections_bound", since = "1.17.0")] -#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)] -pub enum Bound<T> { - /// An inclusive bound. - #[stable(feature = "collections_bound", since = "1.17.0")] - Included(#[stable(feature = "collections_bound", since = "1.17.0")] T), - /// An exclusive bound. - #[stable(feature = "collections_bound", since = "1.17.0")] - Excluded(#[stable(feature = "collections_bound", since = "1.17.0")] T), - /// An infinite endpoint. Indicates that there is no bound in this direction. - #[stable(feature = "collections_bound", since = "1.17.0")] - Unbounded, -} - -impl<T: Clone> Bound<&T> { - /// Map a `Bound<&T>` to a `Bound<T>` by cloning the contents of the bound. - /// - /// # Examples - /// - /// ``` - /// #![feature(bound_cloned)] - /// use std::ops::Bound::*; - /// use std::ops::RangeBounds; - /// - /// assert_eq!((1..12).start_bound(), Included(&1)); - /// assert_eq!((1..12).start_bound().cloned(), Included(1)); - /// ``` - #[unstable(feature = "bound_cloned", issue = "61356")] - pub fn cloned(self) -> Bound<T> { - match self { - Bound::Unbounded => Bound::Unbounded, - Bound::Included(x) => Bound::Included(x.clone()), - Bound::Excluded(x) => Bound::Excluded(x.clone()), - } - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -/// `RangeBounds` is implemented by Rust's built-in range types, produced -/// by range syntax like `..`, `a..`, `..b`, `..=c`, `d..e`, or `f..=g`. -pub trait RangeBounds<T: ?Sized> { - /// Start index bound. - /// - /// Returns the start value as a `Bound`. - /// - /// # Examples - /// - /// ``` - /// # fn main() { - /// use std::ops::Bound::*; - /// use std::ops::RangeBounds; - /// - /// assert_eq!((..10).start_bound(), Unbounded); - /// assert_eq!((3..10).start_bound(), Included(&3)); - /// # } - /// ``` - #[stable(feature = "collections_range", since = "1.28.0")] - fn start_bound(&self) -> Bound<&T>; - - /// End index bound. - /// - /// Returns the end value as a `Bound`. - /// - /// # Examples - /// - /// ``` - /// # fn main() { - /// use std::ops::Bound::*; - /// use std::ops::RangeBounds; - /// - /// assert_eq!((3..).end_bound(), Unbounded); - /// assert_eq!((3..10).end_bound(), Excluded(&10)); - /// # } - /// ``` - #[stable(feature = "collections_range", since = "1.28.0")] - fn end_bound(&self) -> Bound<&T>; - - /// Returns `true` if `item` is contained in the range. - /// - /// # Examples - /// - /// ``` - /// assert!( (3..5).contains(&4)); - /// assert!(!(3..5).contains(&2)); - /// - /// assert!( (0.0..1.0).contains(&0.5)); - /// assert!(!(0.0..1.0).contains(&f32::NAN)); - /// assert!(!(0.0..f32::NAN).contains(&0.5)); - /// assert!(!(f32::NAN..1.0).contains(&0.5)); - #[stable(feature = "range_contains", since = "1.35.0")] - fn contains<U>(&self, item: &U) -> bool - where - T: PartialOrd<U>, - U: ?Sized + PartialOrd<T>, - { - (match self.start_bound() { - Included(ref start) => *start <= item, - Excluded(ref start) => *start < item, - Unbounded => true, - }) && (match self.end_bound() { - Included(ref end) => item <= *end, - Excluded(ref end) => item < *end, - Unbounded => true, - }) - } -} - -use self::Bound::{Excluded, Included, Unbounded}; - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T: ?Sized> RangeBounds<T> for RangeFull { - fn start_bound(&self) -> Bound<&T> { - Unbounded - } - fn end_bound(&self) -> Bound<&T> { - Unbounded - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeFrom<T> { - fn start_bound(&self) -> Bound<&T> { - Included(&self.start) - } - fn end_bound(&self) -> Bound<&T> { - Unbounded - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeTo<T> { - fn start_bound(&self) -> Bound<&T> { - Unbounded - } - fn end_bound(&self) -> Bound<&T> { - Excluded(&self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for Range<T> { - fn start_bound(&self) -> Bound<&T> { - Included(&self.start) - } - fn end_bound(&self) -> Bound<&T> { - Excluded(&self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeInclusive<T> { - fn start_bound(&self) -> Bound<&T> { - Included(&self.start) - } - fn end_bound(&self) -> Bound<&T> { - Included(&self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeToInclusive<T> { - fn start_bound(&self) -> Bound<&T> { - Unbounded - } - fn end_bound(&self) -> Bound<&T> { - Included(&self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for (Bound<T>, Bound<T>) { - fn start_bound(&self) -> Bound<&T> { - match *self { - (Included(ref start), _) => Included(start), - (Excluded(ref start), _) => Excluded(start), - (Unbounded, _) => Unbounded, - } - } - - fn end_bound(&self) -> Bound<&T> { - match *self { - (_, Included(ref end)) => Included(end), - (_, Excluded(ref end)) => Excluded(end), - (_, Unbounded) => Unbounded, - } - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<'a, T: ?Sized + 'a> RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) { - fn start_bound(&self) -> Bound<&T> { - self.0 - } - - fn end_bound(&self) -> Bound<&T> { - self.1 - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeFrom<&T> { - fn start_bound(&self) -> Bound<&T> { - Included(self.start) - } - fn end_bound(&self) -> Bound<&T> { - Unbounded - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeTo<&T> { - fn start_bound(&self) -> Bound<&T> { - Unbounded - } - fn end_bound(&self) -> Bound<&T> { - Excluded(self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for Range<&T> { - fn start_bound(&self) -> Bound<&T> { - Included(self.start) - } - fn end_bound(&self) -> Bound<&T> { - Excluded(self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeInclusive<&T> { - fn start_bound(&self) -> Bound<&T> { - Included(self.start) - } - fn end_bound(&self) -> Bound<&T> { - Included(self.end) - } -} - -#[stable(feature = "collections_range", since = "1.28.0")] -impl<T> RangeBounds<T> for RangeToInclusive<&T> { - fn start_bound(&self) -> Bound<&T> { - Unbounded - } - fn end_bound(&self) -> Bound<&T> { - Included(self.end) - } -} |