Struct BoundedMap 

pub struct BoundedMap<K, V, const MIN: usize, const MAX: usize>(/* private fields */);

Owned key-value map constrained by inclusive entry-count bounds.

BoundedMap<K, V, MIN, MAX> guarantees that the number of entries is always in the range MIN..=MAX and that every key is unique. It is backed by a Vec<(K, V)> in insertion order, so iteration is deterministic and pulls in no hashing or ordering machinery — lookups are a linear scan, which is fine for the small, bounded sizes this type is meant for.

Mutations that would violate the bounds return a CollectionError instead of panicking. Construction rejects duplicate keys with CollectionError::Duplicate.

Const parameters

• MIN: minimum number of entries (inclusive). Use 0 for no lower bound.
• MAX: maximum number of entries (inclusive).

Construction fails with CollectionError::InvalidBounds if MIN > MAX.

Equality

Equality is order-sensitive: two maps with the same entries inserted in a different order are not equal, matching the insertion-order semantics.

Implementations

impl<K, V, const MIN: usize, const MAX: usize> BoundedMap<K, V, MIN, MAX>

pub fn len(&self) -> usize

Returns the number of entries.

pub fn is_empty(&self) -> bool

Returns true if the map contains no entries.

Always returns false when MIN > 0, since construction guarantees at least MIN entries.

pub fn iter(&self) -> Iter<'_, (K, V)>

Returns an iterator over the (K, V) entries in insertion order.

pub fn keys(&self) -> impl Iterator<Item = &K>

Returns an iterator over the keys in insertion order.

pub fn values(&self) -> impl Iterator<Item = &V>

Returns an iterator over the values in insertion order.

pub fn as_slice(&self) -> &[(K, V)]

Returns the entries as a slice in insertion order.

pub fn into_inner(self) -> Vec<(K, V)>

Consumes the wrapper and returns the inner Vec<(K, V)>.

pub const fn min_len() -> usize

Returns the minimum allowed number of entries.

pub const fn max_len() -> usize

Returns the maximum allowed number of entries.

impl<K: PartialEq, V, const MIN: usize, const MAX: usize> BoundedMap<K, V, MIN, MAX>

pub fn new(entries: Vec<(K, V)>) -> CollectionResult<Self>

Creates a BoundedMap from a vector of entries.

Returns an error if the bounds are invalid (MIN > MAX), the entry count is out of range, or two entries share a key.

pub fn insert(&mut self, key: K, value: V) -> CollectionResult<Option<V>>

Inserts a key-value pair.

If the key already exists, its value is replaced and the old value is returned as Ok(Some(old)) (the entry count does not change). If the key is new, it is appended and Ok(None) is returned, unless the map is already at capacity (len == MAX), in which case CollectionError::TooMany is returned and nothing changes.

pub fn remove(&mut self, key: &K) -> CollectionResult<Option<V>>

Removes the entry for key, returning its value.

Returns Ok(None) if the key is absent (no change). Returns CollectionError::TooFew if removing would bring the entry count below MIN, leaving the map unchanged.

pub fn get(&self, key: &K) -> Option<&V>

Returns a reference to the value for key, or None if absent.

pub fn get_mut(&mut self, key: &K) -> Option<&mut V>

Returns a mutable reference to the value for key, or None if absent.

pub fn contains_key(&self, key: &K) -> bool

Returns true if the map contains key.

Trait Implementations

impl<K: Clone, V: Clone, const MIN: usize, const MAX: usize> Clone for BoundedMap<K, V, MIN, MAX>

fn clone(&self) -> BoundedMap<K, V, MIN, MAX>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<K: Debug, V: Debug, const MIN: usize, const MAX: usize> Debug for BoundedMap<K, V, MIN, MAX>

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

Formats the value using the given formatter.

impl<K: Eq, V: Eq, const MIN: usize, const MAX: usize> Eq for BoundedMap<K, V, MIN, MAX>

impl<K, V, const MIN: usize, const MAX: usize> From<BoundedMap<K, V, MIN, MAX>> for Vec<(K, V)>

fn from(value: BoundedMap<K, V, MIN, MAX>) -> Self

Converts to this type from the input type.

impl<K: Hash, V: Hash, const MIN: usize, const MAX: usize> Hash for BoundedMap<K, V, MIN, MAX>

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

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<K: PartialEq, V: PartialEq, const MIN: usize, const MAX: usize> PartialEq for BoundedMap<K, V, MIN, MAX>

fn eq(&self, other: &BoundedMap<K, V, MIN, MAX>) -> 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<K, V, const MIN: usize, const MAX: usize> StructuralPartialEq for BoundedMap<K, V, MIN, MAX>

impl<K: PartialEq, V, const MIN: usize, const MAX: usize> TryFrom<Vec<(K, V)>> for BoundedMap<K, V, MIN, MAX>

type Error = CollectionError

The type returned in the event of a conversion error.

fn try_from(entries: Vec<(K, V)>) -> Result<Self, Self::Error>

Performs the conversion.