Struct Map

pub struct Map<K, V> { /* private fields */ }

Represents a serializable key/value type.

Implementations

impl Map<String, Value>

pub fn new() -> Map<String, Value>

Makes a new, empty Map.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();

// entries can now be inserted into the empty map
map.insert("sesh".to_owned(), "a".into());

pub fn clear(&mut self)

Clears the map, removing all elements.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
a.insert("sesh".to_owned(), "a".into());
a.clear();
assert!(a.is_empty());

pub fn get<Q>(&self, key: &Q) -> Option<&Value>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Returns a reference to the value corresponding to the key.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
assert_eq!(map.get("sesh").and_then(|v| v.as_str()), Some("a"));
assert_eq!(map.get("notexist"), None);

pub fn get_key_value<Q>(&self, key: &Q) -> Option<(&String, &Value)>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Returns the key-value pair matching the given key.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
let entry = map
    .get_key_value("sesh")
    .and_then(|(k, v)| Some(k.as_str()).zip(v.as_str()));
assert_eq!(entry, Some(("sesh", "a")));
assert_eq!(map.get_key_value("notexist"), None);

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

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Returns true if the map contains a value for the specified key.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
assert_eq!(map.contains_key("sesh"), true);
assert_eq!(map.contains_key("notexist"), false);

pub fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut Value>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Returns a mutable reference to the value corresponding to the key.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
if let Some(x) = map.get_mut("sesh") {
    *x = "b".into();
}
assert_eq!(map["sesh"], "b");

pub fn insert(&mut self, key: String, value: Value) -> Option<Value>

Inserts a key-value pair into the map.

If the map did not have this key present, None is returned.

If the map did have this key present, the value is updated, and the old value is returned.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
assert_eq!(map.insert("sesh".to_owned(), "a".into()), None);
assert_eq!(map.is_empty(), false);

map.insert("sesh".to_owned(), "b".into());
let prev = map.insert("sesh".to_owned(), "c".into());
assert_eq!(prev.as_ref().and_then(|v| v.as_str()), Some("b"));
assert_eq!(map["sesh"], "c");

pub fn remove<Q>(&mut self, key: &Q) -> Option<Value>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Removes a key from the map, returning the value at the key if the key was previously in the map.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
assert_eq!(map.remove("sesh").as_ref().and_then(|v| v.as_str()), Some("a"));
assert_eq!(map.remove("sesh"), None);

pub fn remove_entry<Q>(&mut self, key: &Q) -> Option<(String, Value)>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Removes a key from the map, returning the stored key and value if the key was previously in the map.

The key may be any borrowed form of the map’s key type, but the ordering on the borrowed form must match the ordering on the key type.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("sesh".to_owned(), "a".into());
let entry = map.remove_entry("sesh");
assert_eq!(
    entry.as_ref()
        .and_then(|(k, v)| Some(k.as_str()).zip(v.as_str())),
    Some(("sesh", "a"))
);
assert_eq!(map.remove_entry("sesh"), None);

pub fn retain<F>(&mut self, f: F)

where F: FnMut(&String, &mut Value) -> bool,

Retains only the elements specified by the predicate.

In other words, remove all pairs (k, v) for which f(&k, &mut v) returns false.

Examples

use tower_sesh::{value::Map, Value};

let mut map = Map::from_iter([
    ("rust".into(), "a".into()),
    ("sesh".into(), "b".into()),
    ("tower".into(), "c".into()),
]);
// Keep only the elements with keys of length 4.
map.retain(|k, _| k.len() == 4);
let elements = map.into_iter().collect::<Vec<(String, Value)>>();
assert_eq!(
    elements,
    vec![("rust".into(), "a".into()), ("sesh".into(), "b".into())]
);

pub fn append(&mut self, other: &mut Map<String, Value>)

Moves all elements from other into self, leaving other empty.

If a key from other is already present in self, the respective value from self will be overwritten with the respective value from other.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
a.insert("one".to_owned(), "a".into());
a.insert("two".to_owned(), "b".into());
a.insert("three".to_owned(), "c".into()); // Note: Key ("three") also present in b.

let mut b = Map::new();
b.insert("three".to_owned(), "d".into()); // Note: Key ("three") also present in a.
b.insert("four".to_owned(), "e".into());
b.insert("five".to_owned(), "f".into());

a.append(&mut b);

assert_eq!(a.len(), 5);
assert_eq!(b.len(), 0);

assert_eq!(a["one"], "a");
assert_eq!(a["two"], "b");
assert_eq!(a["three"], "d"); // Note: "c" has been overwritten.
assert_eq!(a["four"], "e");
assert_eq!(a["five"], "f");

pub fn entry<S>(&mut self, key: S) -> Entry<'_>

where S: Into<String>,

Gets the given key’s corresponding entry in the map for in-place manipulation.

Examples

use tower_sesh::value::Map;

let mut count = Map::new();

// count the number of occurrences of letters in the vec
for x in ["a", "b", "a", "c", "a", "b"] {
    count.entry(x)
        .and_modify(|curr| *curr = (curr.as_u64().unwrap_or(0) + 1).into())
        .or_insert_with(|| 1.into());
}

assert_eq!(count["a"], 3);
assert_eq!(count["b"], 2);
assert_eq!(count["c"], 1);

pub fn len(&self) -> usize

Returns the number of elements in the map.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
assert_eq!(a.len(), 0);
a.insert("sesh".to_owned(), "a".into());
assert_eq!(a.len(), 1);

pub fn is_empty(&self) -> bool

Returns true if the map contains no elements.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
assert!(a.is_empty());
a.insert("sesh".to_owned(), "a".into());
assert!(!a.is_empty());

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

Gets an iterator over the entries of the map.

Examples

use tower_sesh::value::Map;

let mut map = Map::new();
map.insert("1".to_owned(), "a".into());
map.insert("2".to_owned(), "b".into());
map.insert("3".to_owned(), "c".into());

for (key, value) in map.iter() {
    println!("{key}: {value:?}");
}

let (first_key, first_value) = map.iter().next().unwrap();
assert_eq!((first_key.as_str(), first_value.as_str().unwrap()), ("1", "a"));

pub fn iter_mut(&mut self) -> IterMut<'_>

Gets a mutable iterator over the entries of the map.

Examples

use tower_sesh::value::Map;

let mut map = Map::from_iter([
    ("a".to_owned(), 1.into()),
    ("b".to_owned(), 2.into()),
    ("c".to_owned(), 3.into()),
]);

// add 10 to the value if the key isn't "a"
for (key, value) in map.iter_mut() {
    if key != "a" {
        *value = (value.as_u64().unwrap_or(0) + 10).into();
    }
}

assert_eq!(map["a"], 1);
assert_eq!(map["b"], 12);
assert_eq!(map["c"], 13);

pub fn keys(&self) -> Keys<'_>

Gets an iterator over the keys of the map.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
a.insert("rust".to_owned(), "a".into());
a.insert("sesh".to_owned(), "b".into());

let keys: Vec<_> = a.keys().cloned().collect();
assert_eq!(keys, ["rust", "sesh"]);

pub fn values(&self) -> Values<'_>

Gets an iterator over the values of the map.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
a.insert("rust".to_owned(), "hello".into());
a.insert("sesh".to_owned(), "goodbye".into());

let values: Vec<_> = a.values().cloned().collect();
assert_eq!(values, ["hello", "goodbye"]);

pub fn values_mut(&mut self) -> ValuesMut<'_>

Gets a mutable iterator over the values of the map.

Examples

use tower_sesh::{value::Map, Value};

let mut a = Map::new();
a.insert("rust".to_owned(), "hello".into());
a.insert("sesh".to_owned(), "goodbye".into());

for value in a.values_mut() {
    match value {
        Value::String(s) => s.push_str("!"),
        _ => unimplemented!(),
    }
}

let values: Vec<_> = a.values().cloned().collect();
assert_eq!(values, ["hello!", "goodbye!"]);

pub fn into_values(self) -> IntoValues

Creates a consuming iterator visiting all the values of the map. The map cannot be used after calling this.

Examples

use tower_sesh::value::Map;

let mut a = Map::new();
a.insert("rust".to_owned(), "hello".into());
a.insert("sesh".to_owned(), "goodbye".into());

let values: Vec<_> = a.into_values().collect();
assert_eq!(values, ["hello", "goodbye"]);

Trait Implementations

impl Clone for Map<String, Value>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Map<String, Value>

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

Formats the value using the given formatter.

impl Default for Map<String, Value>

fn default() -> Self

Creates an empty Map.

impl<'de> Deserialize<'de> for Map<String, Value>

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Extend<(String, Value)> for Map<String, Value>

fn extend<T: IntoIterator<Item = (String, Value)>>(&mut self, iter: T)

Extends a collection with the contents of an iterator.

fn extend_one(&mut self, item: A)

🔬This is a nightly-only experimental API. (extend_one)

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

🔬This is a nightly-only experimental API. (extend_one)

Reserves capacity in a collection for the given number of additional elements.

impl From<Map<String, Value>> for Value

fn from(value: Map<String, Value>) -> Self

Convert Map to Value::Map.

Examples

use tower_sesh::{value::Map, Value};

let mut m = Map::new();
m.insert("Lorem".to_owned(), "ipsum".into());
let x: Value = m.into();

impl FromIterator<(String, Value)> for Map<String, Value>

fn from_iter<T: IntoIterator<Item = (String, Value)>>(iter: T) -> Self

Creates a value from an iterator.

impl<Q> Index<&Q> for Map<String, Value>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Access an element of this map. Panics if the given key is not present in the map.

match val {
    Value::String(s) => Some(s.as_str()),
    Value::Array(arr) => arr[0].as_str(),
    Value::Map(map) => map["type"].as_str(),
    _ => None,
}

type Output = Value

The returned type after indexing.

fn index(&self, index: &Q) -> &Self::Output

Performs the indexing (container[index]) operation.

impl<Q> IndexMut<&Q> for Map<String, Value>

where String: Borrow<Q>, Q: ?Sized + Ord + Eq + Hash,

Mutably access an element of this map. Panics if the given key is not present in the map.

map["key"] = Value::String("value".to_owned());

fn index_mut(&mut self, index: &Q) -> &mut Self::Output

Performs the mutable indexing (container[index]) operation.

impl<'a> IntoIterator for &'a Map<String, Value>

type Item = <<&'a Map<String, Value> as IntoIterator>::IntoIter as Iterator>::Item

The type of the elements being iterated over.

type IntoIter = Iter<'a>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'a> IntoIterator for &'a mut Map<String, Value>

type Item = <<&'a mut Map<String, Value> as IntoIterator>::IntoIter as Iterator>::Item

The type of the elements being iterated over.

type IntoIter = IterMut<'a>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl IntoIterator for Map<String, Value>

type Item = <<Map<String, Value> as IntoIterator>::IntoIter as Iterator>::Item

The type of the elements being iterated over.

type IntoIter = IntoIter

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl PartialEq for Map<String, Value>

fn eq(&self, other: &Self) -> 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 Serialize for Map<String, Value>

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

where S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Map<String, Value>