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use crate::fmt; use crate::hash::{Hash, Hasher}; /// 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, 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, 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 /// /// ``` /// use std::f32; /// /// 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)] /// /// use std::f32::NAN; /// assert!(!(3.0..5.0).is_empty()); /// assert!( (3.0..NAN).is_empty()); /// assert!( (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*: Currently, no overflow checking is done for the [`Iterator`] /// implementation; if you use an integer range and the integer overflows, it /// might panic in debug mode or create an endless loop in release mode. **This /// overflow behavior might change in the future.** /// /// # 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 /// /// ``` /// use std::f32; /// /// 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 /// /// ``` /// use std::f32; /// /// 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)] // not Copy -- see #27186 #[stable(feature = "inclusive_range", since = "1.26.0")] pub struct RangeInclusive<Idx> { pub(crate) start: Idx, pub(crate) end: Idx, pub(crate) is_empty: Option<bool>, // This field is: // - `None` when next() or next_back() was never called // - `Some(false)` when `start <= end` assuming no overflow // - `Some(true)` otherwise // The field cannot be a simple `bool` because the `..=` constructor can // accept non-PartialOrd types, also we want the constructor to be const. } trait RangeInclusiveEquality: Sized { fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool; } impl<T> RangeInclusiveEquality for T { #[inline] default fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool { range.is_empty.unwrap_or_default() } } impl<T: PartialOrd> RangeInclusiveEquality for T { #[inline] fn canonicalized_is_empty(range: &RangeInclusive<Self>) -> bool { range.is_empty() } } #[stable(feature = "inclusive_range", since = "1.26.0")] impl<Idx: PartialEq> PartialEq for RangeInclusive<Idx> { #[inline] fn eq(&self, other: &Self) -> bool { self.start == other.start && self.end == other.end && RangeInclusiveEquality::canonicalized_is_empty(self) == RangeInclusiveEquality::canonicalized_is_empty(other) } } #[stable(feature = "inclusive_range", since = "1.26.0")] impl<Idx: Eq> Eq for RangeInclusive<Idx> {} #[stable(feature = "inclusive_range", since = "1.26.0")] impl<Idx: Hash> Hash for RangeInclusive<Idx> { fn hash<H: Hasher>(&self, state: &mut H) { self.start.hash(state); self.end.hash(state); RangeInclusiveEquality::canonicalized_is_empty(self).hash(state); } } 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] pub const fn new(start: Idx, end: Idx) -> Self { Self { start, end, is_empty: None, } } /// 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")] #[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")] #[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)?; Ok(()) } } impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples /// /// ``` /// use std::f32; /// /// 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)] /// /// use std::f32::NAN; /// assert!(!(3.0..=5.0).is_empty()); /// assert!( (3.0..=NAN).is_empty()); /// assert!( (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.is_empty.unwrap_or_else(|| !(self.start <= self.end)) } // If this range's `is_empty` is field is unknown (`None`), update it to be a concrete value. #[inline] pub(crate) fn compute_is_empty(&mut self) { if self.is_empty.is_none() { self.is_empty = Some(!(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 /// /// ``` /// use std::f32; /// /// 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, } #[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 /// /// ``` /// use std::f32; /// /// 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) } }