Rollup merge of #34919 - GuillaumeGomez:btree_map_doc, r=steveklabnik
Add doc for btree_map types Part of #29348. r? @steveklabnik
This commit is contained in:
commit
d62f8dde76
@ -313,6 +313,10 @@ pub struct RangeMut<'a, K: 'a, V: 'a> {
|
||||
}
|
||||
|
||||
/// A view into a single entry in a map, which may either be vacant or occupied.
|
||||
/// This enum is constructed from the [`entry`] method on [`BTreeMap`].
|
||||
///
|
||||
/// [`BTreeMap`]: struct.BTreeMap.html
|
||||
/// [`entry`]: struct.BTreeMap.html#method.entry
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub enum Entry<'a, K: 'a, V: 'a> {
|
||||
/// A vacant Entry
|
||||
@ -340,7 +344,9 @@ impl<'a, K: 'a + Debug + Ord, V: 'a + Debug> Debug for Entry<'a, K, V> {
|
||||
}
|
||||
}
|
||||
|
||||
/// A vacant Entry.
|
||||
/// A vacant Entry. It is part of the [`Entry`] enum.
|
||||
///
|
||||
/// [`Entry`]: enum.Entry.html
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub struct VacantEntry<'a, K: 'a, V: 'a> {
|
||||
key: K,
|
||||
@ -360,7 +366,9 @@ impl<'a, K: 'a + Debug + Ord, V: 'a> Debug for VacantEntry<'a, K, V> {
|
||||
}
|
||||
}
|
||||
|
||||
/// An occupied Entry.
|
||||
/// An occupied Entry. It is part of the [`Entry`] enum.
|
||||
///
|
||||
/// [`Entry`]: enum.Entry.html
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub struct OccupiedEntry<'a, K: 'a, V: 'a> {
|
||||
handle: Handle<NodeRef<marker::Mut<'a>, K, V, marker::LeafOrInternal>, marker::KV>,
|
||||
@ -1890,6 +1898,17 @@ impl<K, V> BTreeMap<K, V> {
|
||||
impl<'a, K: Ord, V> Entry<'a, K, V> {
|
||||
/// Ensures a value is in the entry by inserting the default if empty, and returns
|
||||
/// a mutable reference to the value in the entry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// assert_eq!(map["poneyland"], 12);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn or_insert(self, default: V) -> &'a mut V {
|
||||
match self {
|
||||
@ -1900,6 +1919,19 @@ impl<'a, K: Ord, V> Entry<'a, K, V> {
|
||||
|
||||
/// Ensures a value is in the entry by inserting the result of the default function if empty,
|
||||
/// and returns a mutable reference to the value in the entry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, String> = BTreeMap::new();
|
||||
/// let s = "hoho".to_owned();
|
||||
///
|
||||
/// map.entry("poneyland").or_insert_with(|| s);
|
||||
///
|
||||
/// assert_eq!(map["poneyland"], "hoho".to_owned());
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn or_insert_with<F: FnOnce() -> V>(self, default: F) -> &'a mut V {
|
||||
match self {
|
||||
@ -1909,6 +1941,15 @@ impl<'a, K: Ord, V> Entry<'a, K, V> {
|
||||
}
|
||||
|
||||
/// Returns a reference to this entry's key.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// assert_eq!(map.entry("poneyland").key(), &"poneyland");
|
||||
/// ```
|
||||
#[stable(feature = "map_entry_keys", since = "1.10.0")]
|
||||
pub fn key(&self) -> &K {
|
||||
match *self {
|
||||
@ -1921,12 +1962,36 @@ impl<'a, K: Ord, V> Entry<'a, K, V> {
|
||||
impl<'a, K: Ord, V> VacantEntry<'a, K, V> {
|
||||
/// Gets a reference to the key that would be used when inserting a value
|
||||
/// through the VacantEntry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// assert_eq!(map.entry("poneyland").key(), &"poneyland");
|
||||
/// ```
|
||||
#[stable(feature = "map_entry_keys", since = "1.10.0")]
|
||||
pub fn key(&self) -> &K {
|
||||
&self.key
|
||||
}
|
||||
|
||||
/// Take ownership of the key.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// #![feature(map_entry_recover_keys)]
|
||||
///
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
///
|
||||
/// if let Entry::Vacant(v) = map.entry("poneyland") {
|
||||
/// v.into_key();
|
||||
/// }
|
||||
/// ```
|
||||
#[unstable(feature = "map_entry_recover_keys", issue = "34285")]
|
||||
pub fn into_key(self) -> K {
|
||||
self.key
|
||||
@ -1934,6 +1999,21 @@ impl<'a, K: Ord, V> VacantEntry<'a, K, V> {
|
||||
|
||||
/// Sets the value of the entry with the VacantEntry's key,
|
||||
/// and returns a mutable reference to it.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut count: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
///
|
||||
/// // count the number of occurrences of letters in the vec
|
||||
/// for x in vec!["a","b","a","c","a","b"] {
|
||||
/// *count.entry(x).or_insert(0) += 1;
|
||||
/// }
|
||||
///
|
||||
/// assert_eq!(count["a"], 3);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn insert(self, value: V) -> &'a mut V {
|
||||
*self.length += 1;
|
||||
@ -1979,30 +2059,106 @@ impl<'a, K: Ord, V> VacantEntry<'a, K, V> {
|
||||
|
||||
impl<'a, K: Ord, V> OccupiedEntry<'a, K, V> {
|
||||
/// Gets a reference to the key in the entry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
/// assert_eq!(map.entry("poneyland").key(), &"poneyland");
|
||||
/// ```
|
||||
#[stable(feature = "map_entry_keys", since = "1.10.0")]
|
||||
pub fn key(&self) -> &K {
|
||||
self.handle.reborrow().into_kv().0
|
||||
}
|
||||
|
||||
/// Take ownership of the key and value from the map.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// #![feature(map_entry_recover_keys)]
|
||||
///
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// if let Entry::Occupied(o) = map.entry("poneyland") {
|
||||
/// // We delete the entry from the map.
|
||||
/// o.remove_pair();
|
||||
/// }
|
||||
///
|
||||
/// // If now try to get the value, it will panic:
|
||||
/// // println!("{}", map["poneyland"]);
|
||||
/// ```
|
||||
#[unstable(feature = "map_entry_recover_keys", issue = "34285")]
|
||||
pub fn remove_pair(self) -> (K, V) {
|
||||
self.remove_kv()
|
||||
}
|
||||
|
||||
/// Gets a reference to the value in the entry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// if let Entry::Occupied(o) = map.entry("poneyland") {
|
||||
/// assert_eq!(o.get(), &12);
|
||||
/// }
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn get(&self) -> &V {
|
||||
self.handle.reborrow().into_kv().1
|
||||
}
|
||||
|
||||
/// Gets a mutable reference to the value in the entry.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// assert_eq!(map["poneyland"], 12);
|
||||
/// if let Entry::Occupied(mut o) = map.entry("poneyland") {
|
||||
/// *o.get_mut() += 10;
|
||||
/// }
|
||||
/// assert_eq!(map["poneyland"], 22);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn get_mut(&mut self) -> &mut V {
|
||||
self.handle.kv_mut().1
|
||||
}
|
||||
|
||||
/// Converts the entry into a mutable reference to its value.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// assert_eq!(map["poneyland"], 12);
|
||||
/// if let Entry::Occupied(o) = map.entry("poneyland") {
|
||||
/// *o.into_mut() += 10;
|
||||
/// }
|
||||
/// assert_eq!(map["poneyland"], 22);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn into_mut(self) -> &'a mut V {
|
||||
self.handle.into_kv_mut().1
|
||||
@ -2010,12 +2166,43 @@ impl<'a, K: Ord, V> OccupiedEntry<'a, K, V> {
|
||||
|
||||
/// Sets the value of the entry with the OccupiedEntry's key,
|
||||
/// and returns the entry's old value.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// if let Entry::Occupied(mut o) = map.entry("poneyland") {
|
||||
/// assert_eq!(o.insert(15), 12);
|
||||
/// }
|
||||
/// assert_eq!(map["poneyland"], 15);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn insert(&mut self, value: V) -> V {
|
||||
mem::replace(self.get_mut(), value)
|
||||
}
|
||||
|
||||
/// Takes the value of the entry out of the map, and returns it.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```
|
||||
/// use std::collections::BTreeMap;
|
||||
/// use std::collections::btree_map::Entry;
|
||||
///
|
||||
/// let mut map: BTreeMap<&str, usize> = BTreeMap::new();
|
||||
/// map.entry("poneyland").or_insert(12);
|
||||
///
|
||||
/// if let Entry::Occupied(o) = map.entry("poneyland") {
|
||||
/// assert_eq!(o.remove(), 12);
|
||||
/// }
|
||||
/// // If we try to get "poneyland"'s value, it'll panic:
|
||||
/// // println!("{}", map["poneyland"]);
|
||||
/// ```
|
||||
#[stable(feature = "rust1", since = "1.0.0")]
|
||||
pub fn remove(self) -> V {
|
||||
self.remove_kv().1
|
||||
|
Loading…
Reference in New Issue
Block a user