Enum 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>

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)

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

pub fn map<U, F>(self, f: F) -> Bound<U>

where F: FnOnce(T) -> U,

Maps a Bound<T> to a Bound<U> by applying a function to the contained value (including both Included and Excluded), returning a Bound of the same kind.

Examples

use std::ops::Bound::*;

let bound_string = Included("Hello, World!");

assert_eq!(bound_string.map(|s| s.len()), Included(13));

use std::ops::Bound;
use Bound::*;

let unbounded_string: Bound<String> = Unbounded;

assert_eq!(unbounded_string.map(|s| s.len()), Unbounded);

impl<T> Bound<&T>

where T: Clone,

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

Map a Bound<&T> to a Bound<T> by cloning the contents of the bound.

Examples

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<A> Arbitrary for Bound<A>

where A: Arbitrary,

type Parameters = <A as Arbitrary>::Parameters

The type of parameters that arbitrary_with accepts for configuration of the generated Strategy. Parameters must implement Default.

type Strategy = TupleUnion<((u32, Arc<Map<Arc<<A as Arbitrary>::Strategy>, fn(<Arc<<A as Arbitrary>::Strategy> as Strategy>::Value) -> Bound<A>>>), (u32, Arc<Map<Arc<<A as Arbitrary>::Strategy>, fn(<Arc<<A as Arbitrary>::Strategy> as Strategy>::Value) -> Bound<A>>>), (u32, Arc<LazyJust<Bound<A>, fn() -> Bound<A>>>))>

The type of Strategy used to generate values of type Self.

fn arbitrary_with( args: <Bound<A> as Arbitrary>::Parameters, ) -> <Bound<A> as Arbitrary>::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self). The strategy is passed the arguments given in args.

fn arbitrary() -> Self::Strategy

Generates a Strategy for producing arbitrary values of type the implementing type (Self).

impl<A> ArbitraryF1<A> for Bound<A>

where A: Debug + 'static,

type Parameters = ()

The type of parameters that lift1_with accepts for configuration of the lifted and generated Strategy. Parameters must implement Default.

fn lift1_with<S>( base: S, _args: <Bound<A> as ArbitraryF1<A>>::Parameters, ) -> BoxedStrategy<Bound<A>>

where S: Strategy<Value = A> + 'static,

Lifts a given Strategy to a new Strategy for the (presumably) bigger type. This is useful for lifting a Strategy for SomeType to a container such as Vec of SomeType. The composite strategy is passed the arguments given in args.

fn lift1<AS>(base: AS) -> BoxedStrategy<Self>

where AS: Strategy<Value = A> + 'static,

Lifts a given Strategy to a new Strategy for the (presumably) bigger type. This is useful for lifting a Strategy for SomeType to a container such as Vec<SomeType>.

impl<T> Clone for Bound<T>

where T: Clone,

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 for Bound<T>

where T: Debug,

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

Formats the value using the given formatter.

impl<'de, T> Deserialize<'de> for Bound<T>

where T: Deserialize<'de>,

fn deserialize<D>( deserializer: D, ) -> Result<Bound<T>, <D as Deserializer<'de>>::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl<T> Hash for Bound<T>

where T: Hash,

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

where __H: Hasher,

Feeds this value into the given Hasher.

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

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl<T> PartialEq for Bound<T>

where T: PartialEq,

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

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl<T> Serialize for Bound<T>

where T: Serialize,

fn serialize<S>( &self, serializer: S, ) -> Result<<S as Serializer>::Ok, <S as Serializer>::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl<T> Copy for Bound<T>

where T: Copy,

impl<T> Eq for Bound<T>

where T: Eq,

impl<T> StructuralPartialEq for Bound<T>