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Diffstat (limited to 'vendor/multimap/src/entry.rs')
| -rw-r--r-- | vendor/multimap/src/entry.rs | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/vendor/multimap/src/entry.rs b/vendor/multimap/src/entry.rs new file mode 100644 index 00000000..f5420491 --- /dev/null +++ b/vendor/multimap/src/entry.rs @@ -0,0 +1,127 @@ +// Copyright (c) 2016 multimap developers +// +// Licensed under the Apache License, Version 2.0 +// <LICENSE-APACHE or https://www.apache.org/licenses/LICENSE-2.0> or the MIT +// license <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. All files in the project carrying such notice may not be copied, +// modified, or distributed except according to those terms. + +use std::collections::hash_map::OccupiedEntry as HashMapOccupiedEntry; +use std::collections::hash_map::VacantEntry as HashMapVacantEntry; + +/// A view into a single occupied location in a MultiMap. +pub struct OccupiedEntry<'a, K: 'a, V: 'a> { + #[doc(hidden)] + pub inner: HashMapOccupiedEntry<'a, K, Vec<V>>, +} + +/// A view into a single empty location in a MultiMap. +pub struct VacantEntry<'a, K: 'a, V: 'a> { + #[doc(hidden)] + pub inner: HashMapVacantEntry<'a, K, Vec<V>>, +} + +/// A view into a single location in a map, which may be vacant or occupied. +pub enum Entry<'a, K: 'a, V: 'a> { + /// An occupied Entry. + Occupied(OccupiedEntry<'a, K, V>), + + /// A vacant Entry. + Vacant(VacantEntry<'a, K, V>), +} + +impl<'a, K: 'a, V: 'a> OccupiedEntry<'a, K, V> { + /// Gets a reference to the first item in value in the vector corresponding to entry. + /// + /// # Panics + /// + /// This method will panic if the key has zero values. + pub fn get(&self) -> &V { + self.inner.get().first().expect("no values in entry") + } + + /// Gets a reference to the values (vector) corresponding to entry. + pub fn get_vec(&self) -> &Vec<V> { + self.inner.get() + } + + /// Gets a mut reference to the first item in value in the vector corresponding to entry. + /// + /// # Panics + /// + /// This method will panic if the key has zero values. + pub fn get_mut(&mut self) -> &mut V { + self.inner + .get_mut() + .first_mut() + .expect("no values in entry") + } + + /// Gets a mut reference to the values (vector) corresponding to entry. + pub fn get_vec_mut(&mut self) -> &mut Vec<V> { + self.inner.get_mut() + } + + /// Converts the OccupiedEntry into a mutable reference to the first item in value in the entry + /// with a lifetime bound to the map itself + pub fn into_mut(self) -> &'a mut V { + &mut self.inner.into_mut()[0] + } + + /// Converts the OccupiedEntry into a mutable reference to the values (vector) in the entry + /// with a lifetime bound to the map itself + pub fn into_vec_mut(self) -> &'a mut Vec<V> { + self.inner.into_mut() + } + + /// Inserts a new value onto the vector of the entry. + pub fn insert(&mut self, value: V) { + self.get_vec_mut().push(value); + } + + /// Extends the existing vector with the specified values. + pub fn insert_vec(&mut self, values: Vec<V>) { + self.get_vec_mut().extend(values); + } + + /// Takes the values (vector) out of the entry, and returns it + pub fn remove(self) -> Vec<V> { + self.inner.remove() + } +} + +impl<'a, K: 'a, V: 'a> VacantEntry<'a, K, V> { + /// Sets the first value in the vector of the entry with the VacantEntry's key, + /// and returns a mutable reference to it. + pub fn insert(self, value: V) -> &'a mut V { + &mut self.inner.insert(vec![value])[0] + } + + /// Sets values in the entry with the VacantEntry's key, + /// and returns a mutable reference to it. + pub fn insert_vec(self, values: Vec<V>) -> &'a mut Vec<V> { + self.inner.insert(values) + } +} + +impl<'a, K: 'a, V: 'a> 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. This will return a mutable reference to the + /// first value in the vector corresponding to the specified key. + pub fn or_insert(self, default: V) -> &'a mut V { + match self { + Entry::Occupied(entry) => entry.into_mut(), + Entry::Vacant(entry) => entry.insert(default), + } + } + + /// Ensures a value is in the entry by inserting the default values if empty, and returns + /// a mutable reference to the values (the corresponding vector to the specified key) in + /// the entry. + pub fn or_insert_vec(self, defaults: Vec<V>) -> &'a mut Vec<V> { + match self { + Entry::Occupied(entry) => entry.into_vec_mut(), + Entry::Vacant(entry) => entry.insert_vec(defaults), + } + } +} |
