Enum core::ops::Bound

pub enum Bound<T> {
    Included(T),
    Excluded(T),
    Unbounded,
}

An endpoint of a range of keys.

Examples

Bounds 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 Bounds 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());

Variants

Included(T)

An inclusive bound.

Excluded(T)

An exclusive bound.

Unbounded

An infinite endpoint. Indicates that there is no bound in this direction.

Implementations

impl<T> Bound<T>

pub fn as_ref(&self) -> Bound<&T>

🔬 This is a nightly-only experimental API. (bound_as_ref #80996)

Converts from &Bound<T> to Bound<&T>.

pub fn as_mut(&mut self) -> Bound<&mut T>

🔬 This is a nightly-only experimental API. (bound_as_ref #80996)

Converts from &mut Bound<T> to Bound<&T>.

impl<T: Clone> Bound<&T>

pub fn cloned(self) -> Bound<T>

🔬 This is a nightly-only experimental API. (bound_cloned #61356)

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));

Trait Implementations

impl<T: Clone> Clone for Bound<T>

fn clone(&self) -> Bound<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for Bound<T>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<T: Hash> Hash for Bound<T>

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H: Hasher>(data: &[Self], state: &mut H) where
    Self: Sized, 

Feeds a slice of this type into the given Hasher.

impl<T: PartialEq> PartialEq<Bound<T>> for Bound<T>

fn eq(&self, other: &Bound<T>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Bound<T>) -> bool

This method tests for !=.

impl<T: Copy> Copy for Bound<T>

impl<T: Eq> Eq for Bound<T>

impl<T> StructuralEq for Bound<T>

impl<T> StructuralPartialEq for Bound<T>