Struct core_traits::StructuredMap

pub struct StructuredMap(pub IndexMap<ValueRc<Keyword>, Binding>);

A pull expression expands a binding into a structure. The returned structure associates attributes named in the input or retrieved from the store with values. This association is a StructuredMap.

Note that 'attributes' in Datomic's case can mean:

• Reversed attribute keywords (:artist/_country).
• An alias using :as (:artist/name :as "Band name").

We entirely support the former, and partially support the latter -- you can alias using a different keyword only.

Methods

impl StructuredMap

pub fn insert<N, B>(&mut self, name: N, value: B) where
    N: Into<ValueRc<Keyword>>,
    B: Into<Binding>, 

Methods from Deref<Target = IndexMap<ValueRc<Keyword>, Binding>>

pub fn len(&self) -> usize

Return the number of key-value pairs in the map.

Computes in O(1) time.

pub fn is_empty(&self) -> bool

Returns true if the map contains no elements.

Computes in O(1) time.

Important traits for &'a mut R

impl<'a, R> Read for &'a mut R where
    R: Read + ?Sized, impl<'a, W> Write for &'a mut W where
    W: Write + ?Sized, impl<'a, I> Iterator for &'a mut I where
    I: Iterator + ?Sized,  type Item = <I as Iterator>::Item;

pub fn hasher(&self) -> &S where
    S: BuildHasher, 

Return a reference to the map's BuildHasher.

pub fn capacity(&self) -> usize

Computes in O(1) time.

Important traits for Iter<'a, K, V>

impl<'a, K, V> Iterator for Iter<'a, K, V> type Item = (&'a K, &'a V);

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

Return an iterator over the key-value pairs of the map, in their order

Important traits for Keys<'a, K, V>

impl<'a, K, V> Iterator for Keys<'a, K, V> type Item = &'a K;

pub fn keys(&self) -> Keys<K, V>

Return an iterator over the keys of the map, in their order

Important traits for Values<'a, K, V>

impl<'a, K, V> Iterator for Values<'a, K, V> type Item = &'a V;

pub fn values(&self) -> Values<K, V>

Return an iterator over the values of the map, in their order

pub fn contains_key<Q>(&self, key: &Q) -> bool where
    Q: Hash + Equivalent<K> + ?Sized, 

Return true if an equivalent to key exists in the map.

Computes in O(1) time (average).

pub fn get<Q>(&self, key: &Q) -> Option<&V> where
    Q: Hash + Equivalent<K> + ?Sized, 

Return a reference to the value stored for key, if it is present, else None.

Computes in O(1) time (average).

pub fn get_full<Q>(&self, key: &Q) -> Option<(usize, &K, &V)> where
    Q: Hash + Equivalent<K> + ?Sized, 

Return item index, key and value

pub fn get_index(&self, index: usize) -> Option<(&K, &V)>

Get a key-value pair by index

Valid indices are 0 <= index < self.len()

Computes in O(1) time.

Trait Implementations

impl From<StructuredMap> for Binding

fn from(value: StructuredMap) -> Self

Performs the conversion.

impl Clone for StructuredMap

fn clone(&self) -> StructuredMap

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for StructuredMap

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Default for StructuredMap

fn default() -> StructuredMap

Returns the "default value" for a type.

impl Eq for StructuredMap

impl PartialEq for StructuredMap

fn eq(&self, __arg_0: &StructuredMap) -> bool

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

fn ne(&self, __arg_0: &StructuredMap) -> bool

This method tests for !=.

impl Deref for StructuredMap

type Target = IndexMap<ValueRc<Keyword>, Binding>

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl From<IndexMap<ValueRc<Keyword>, Binding>> for StructuredMap

fn from(src: IndexMap<ValueRc<Keyword>, Binding>) -> Self

Performs the conversion.

impl<T> From<Vec<(Keyword, T)>> for StructuredMap where
    T: Into<Binding>, 

fn from(value: Vec<(Keyword, T)>) -> Self

Performs the conversion.