Source code
Revision control
Copy as Markdown
Other Tools
//! An order-preserving immutable map constructed at compile time.
use core::fmt;
use core::iter::FusedIterator;
use core::iter::IntoIterator;
use core::ops::Index;
use core::slice;
use phf_shared::{self, HashKey, PhfBorrow, PhfHash};
/// An order-preserving immutable map constructed at compile time.
///
/// Unlike a `Map`, iteration order is guaranteed to match the definition
/// order.
///
/// ## Note
///
/// The fields of this struct are public so that they may be initialized by the
/// `phf_ordered_map!` macro and code generation. They are subject to change at
/// any time and should never be accessed directly.
pub struct OrderedMap<K: 'static, V: 'static> {
#[doc(hidden)]
pub key: HashKey,
#[doc(hidden)]
pub disps: &'static [(u32, u32)],
#[doc(hidden)]
pub idxs: &'static [usize],
#[doc(hidden)]
pub entries: &'static [(K, V)],
}
impl<K, V> fmt::Debug for OrderedMap<K, V>
where
K: fmt::Debug,
V: fmt::Debug,
{
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_map().entries(self.entries()).finish()
}
}
impl<'a, K, V, T: ?Sized> Index<&'a T> for OrderedMap<K, V>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
type Output = V;
fn index(&self, k: &'a T) -> &V {
self.get(k).expect("invalid key")
}
}
impl<K, V> OrderedMap<K, V> {
/// Returns the number of entries in the `OrderedMap`.
#[inline]
pub const fn len(&self) -> usize {
self.entries.len()
}
/// Returns true if the `OrderedMap` is empty.
#[inline]
pub const fn is_empty(&self) -> bool {
self.len() == 0
}
/// Returns a reference to the value that `key` maps to.
pub fn get<T: ?Sized>(&self, key: &T) -> Option<&V>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
self.get_entry(key).map(|e| e.1)
}
/// Returns a reference to the map's internal static instance of the given
/// key.
///
/// This can be useful for interning schemes.
pub fn get_key<T: ?Sized>(&self, key: &T) -> Option<&K>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
self.get_entry(key).map(|e| e.0)
}
/// Determines if `key` is in the `OrderedMap`.
pub fn contains_key<T: ?Sized>(&self, key: &T) -> bool
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
self.get(key).is_some()
}
/// Returns the index of the key within the list used to initialize
/// the ordered map.
pub fn get_index<T: ?Sized>(&self, key: &T) -> Option<usize>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
self.get_internal(key).map(|(i, _)| i)
}
/// Returns references to both the key and values at an index
/// within the list used to initialize the ordered map. See `.get_index(key)`.
pub fn index(&self, index: usize) -> Option<(&K, &V)> {
self.entries.get(index).map(|&(ref k, ref v)| (k, v))
}
/// Like `get`, but returns both the key and the value.
pub fn get_entry<T: ?Sized>(&self, key: &T) -> Option<(&K, &V)>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
self.get_internal(key).map(|(_, e)| e)
}
fn get_internal<T: ?Sized>(&self, key: &T) -> Option<(usize, (&K, &V))>
where
T: Eq + PhfHash,
K: PhfBorrow<T>,
{
if self.disps.is_empty() {
return None;
} //Prevent panic on empty map
let hashes = phf_shared::hash(key, &self.key);
let idx_index = phf_shared::get_index(&hashes, self.disps, self.idxs.len());
let idx = self.idxs[idx_index as usize];
let entry = &self.entries[idx];
let b: &T = entry.0.borrow();
if b == key {
Some((idx, (&entry.0, &entry.1)))
} else {
None
}
}
/// Returns an iterator over the key/value pairs in the map.
///
/// Entries are returned in the same order in which they were defined.
pub fn entries(&self) -> Entries<'_, K, V> {
Entries {
iter: self.entries.iter(),
}
}
/// Returns an iterator over the keys in the map.
///
/// Keys are returned in the same order in which they were defined.
pub fn keys(&self) -> Keys<'_, K, V> {
Keys {
iter: self.entries(),
}
}
/// Returns an iterator over the values in the map.
///
/// Values are returned in the same order in which they were defined.
pub fn values(&self) -> Values<'_, K, V> {
Values {
iter: self.entries(),
}
}
}
impl<'a, K, V> IntoIterator for &'a OrderedMap<K, V> {
type Item = (&'a K, &'a V);
type IntoIter = Entries<'a, K, V>;
fn into_iter(self) -> Entries<'a, K, V> {
self.entries()
}
}
/// An iterator over the entries in a `OrderedMap`.
pub struct Entries<'a, K, V> {
iter: slice::Iter<'a, (K, V)>,
}
impl<'a, K, V> Clone for Entries<'a, K, V> {
#[inline]
fn clone(&self) -> Self {
Self {
iter: self.iter.clone(),
}
}
}
impl<'a, K, V> fmt::Debug for Entries<'a, K, V>
where
K: fmt::Debug,
V: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_list().entries(self.clone()).finish()
}
}
impl<'a, K, V> Iterator for Entries<'a, K, V> {
type Item = (&'a K, &'a V);
fn next(&mut self) -> Option<(&'a K, &'a V)> {
self.iter.next().map(|e| (&e.0, &e.1))
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a, K, V> DoubleEndedIterator for Entries<'a, K, V> {
fn next_back(&mut self) -> Option<(&'a K, &'a V)> {
self.iter.next_back().map(|e| (&e.0, &e.1))
}
}
impl<'a, K, V> ExactSizeIterator for Entries<'a, K, V> {}
impl<'a, K, V> FusedIterator for Entries<'a, K, V> {}
/// An iterator over the keys in a `OrderedMap`.
pub struct Keys<'a, K, V> {
iter: Entries<'a, K, V>,
}
impl<'a, K, V> Clone for Keys<'a, K, V> {
#[inline]
fn clone(&self) -> Self {
Self {
iter: self.iter.clone(),
}
}
}
impl<'a, K, V> fmt::Debug for Keys<'a, K, V>
where
K: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_list().entries(self.clone()).finish()
}
}
impl<'a, K, V> Iterator for Keys<'a, K, V> {
type Item = &'a K;
fn next(&mut self) -> Option<&'a K> {
self.iter.next().map(|e| e.0)
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a, K, V> DoubleEndedIterator for Keys<'a, K, V> {
fn next_back(&mut self) -> Option<&'a K> {
self.iter.next_back().map(|e| e.0)
}
}
impl<'a, K, V> ExactSizeIterator for Keys<'a, K, V> {}
impl<'a, K, V> FusedIterator for Keys<'a, K, V> {}
/// An iterator over the values in a `OrderedMap`.
pub struct Values<'a, K, V> {
iter: Entries<'a, K, V>,
}
impl<'a, K, V> Clone for Values<'a, K, V> {
#[inline]
fn clone(&self) -> Self {
Self {
iter: self.iter.clone(),
}
}
}
impl<'a, K, V> fmt::Debug for Values<'a, K, V>
where
V: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_list().entries(self.clone()).finish()
}
}
impl<'a, K, V> Iterator for Values<'a, K, V> {
type Item = &'a V;
fn next(&mut self) -> Option<&'a V> {
self.iter.next().map(|e| e.1)
}
fn size_hint(&self) -> (usize, Option<usize>) {
self.iter.size_hint()
}
}
impl<'a, K, V> DoubleEndedIterator for Values<'a, K, V> {
fn next_back(&mut self) -> Option<&'a V> {
self.iter.next_back().map(|e| e.1)
}
}
impl<'a, K, V> ExactSizeIterator for Values<'a, K, V> {}
impl<'a, K, V> FusedIterator for Values<'a, K, V> {}