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Move RangeArgument and Bound to libcore.
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Clar Charr committed Apr 24, 2017
1 parent 968ae7b commit 688cbda
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53 changes: 2 additions & 51 deletions src/libcollections/lib.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -136,60 +136,11 @@ mod std {
pub use core::ops; // RangeFull
}

/// An endpoint of a range of keys.
///
/// # Examples
///
/// `Bound`s are range endpoints:
///
/// ```
/// #![feature(collections_range)]
///
/// use std::collections::range::RangeArgument;
/// use std::collections::Bound::*;
///
/// assert_eq!((..100).start(), Unbounded);
/// assert_eq!((1..12).start(), Included(&1));
/// assert_eq!((1..12).end(), 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::collections::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`]: 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(T),
/// An exclusive bound.
#[stable(feature = "collections_bound", since = "1.17.0")]
Excluded(T),
/// An infinite endpoint. Indicates that there is no bound in this direction.
#[stable(feature = "collections_bound", since = "1.17.0")]
Unbounded,
}

/// An intermediate trait for specialization of `Extend`.
#[doc(hidden)]
trait SpecExtend<I: IntoIterator> {
/// Extends `self` with the contents of the given iterator.
fn spec_extend(&mut self, iter: I);
}

pub use core::ops::Bound;
146 changes: 1 addition & 145 deletions src/libcollections/range.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -8,151 +8,7 @@
// option. This file may not be copied, modified, or distributed
// except according to those terms.

#![unstable(feature = "collections_range",
reason = "waiting for dust to settle on inclusive ranges",
issue = "30877")]

//! Range syntax.
use core::ops::{RangeFull, Range, RangeTo, RangeFrom, RangeInclusive, RangeToInclusive};
use Bound::{self, Excluded, Included, Unbounded};

/// `RangeArgument` is implemented by Rust's built-in range types, produced
/// by range syntax like `..`, `a..`, `..b` or `c..d`.
pub trait RangeArgument<T: ?Sized> {
/// Start index bound.
///
/// Returns the start value as a `Bound`.
///
/// # Examples
///
/// ```
/// #![feature(collections)]
/// #![feature(collections_range)]
///
/// extern crate collections;
///
/// # fn main() {
/// use collections::range::RangeArgument;
/// use collections::Bound::*;
///
/// assert_eq!((..10).start(), Unbounded);
/// assert_eq!((3..10).start(), Included(&3));
/// # }
/// ```
fn start(&self) -> Bound<&T>;

/// End index bound.
///
/// Returns the end value as a `Bound`.
///
/// # Examples
///
/// ```
/// #![feature(collections)]
/// #![feature(collections_range)]
///
/// extern crate collections;
///
/// # fn main() {
/// use collections::range::RangeArgument;
/// use collections::Bound::*;
///
/// assert_eq!((3..).end(), Unbounded);
/// assert_eq!((3..10).end(), Excluded(&10));
/// # }
/// ```
fn end(&self) -> Bound<&T>;
}

// FIXME add inclusive ranges to RangeArgument

impl<T: ?Sized> RangeArgument<T> for RangeFull {
fn start(&self) -> Bound<&T> {
Unbounded
}
fn end(&self) -> Bound<&T> {
Unbounded
}
}

impl<T> RangeArgument<T> for RangeFrom<T> {
fn start(&self) -> Bound<&T> {
Included(&self.start)
}
fn end(&self) -> Bound<&T> {
Unbounded
}
}

impl<T> RangeArgument<T> for RangeTo<T> {
fn start(&self) -> Bound<&T> {
Unbounded
}
fn end(&self) -> Bound<&T> {
Excluded(&self.end)
}
}

impl<T> RangeArgument<T> for Range<T> {
fn start(&self) -> Bound<&T> {
Included(&self.start)
}
fn end(&self) -> Bound<&T> {
Excluded(&self.end)
}
}

#[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
impl<T> RangeArgument<T> for RangeInclusive<T> {
fn start(&self) -> Bound<&T> {
match *self {
RangeInclusive::Empty{ ref at } => Included(at),
RangeInclusive::NonEmpty { ref start, .. } => Included(start),
}
}
fn end(&self) -> Bound<&T> {
match *self {
RangeInclusive::Empty{ ref at } => Excluded(at),
RangeInclusive::NonEmpty { ref end, .. } => Included(end),
}
}
}

#[unstable(feature = "inclusive_range", reason = "recently added, follows RFC", issue = "28237")]
impl<T> RangeArgument<T> for RangeToInclusive<T> {
fn start(&self) -> Bound<&T> {
Unbounded
}
fn end(&self) -> Bound<&T> {
Included(&self.end)
}
}

impl<T> RangeArgument<T> for (Bound<T>, Bound<T>) {
fn start(&self) -> Bound<&T> {
match *self {
(Included(ref start), _) => Included(start),
(Excluded(ref start), _) => Excluded(start),
(Unbounded, _) => Unbounded,
}
}

fn end(&self) -> Bound<&T> {
match *self {
(_, Included(ref end)) => Included(end),
(_, Excluded(ref end)) => Excluded(end),
(_, Unbounded) => Unbounded,
}
}
}

impl<'a, T: ?Sized + 'a> RangeArgument<T> for (Bound<&'a T>, Bound<&'a T>) {
fn start(&self) -> Bound<&T> {
self.0
}

fn end(&self) -> Bound<&T> {
self.1
}
}
pub use core::ops::RangeArgument;
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