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// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
use crate::ZeroSlice;
use core::cmp::Ordering;
use core::fmt;
use crate::map::ZeroMapKV;
use crate::map::ZeroVecLike;
use crate::map2d::ZeroMap2dCursor;
/// A borrowed-only version of [`ZeroMap2d`](super::ZeroMap2d)
///
/// This is useful for fully-zero-copy deserialization from non-human-readable
/// serialization formats. It also has the advantage that it can return references that live for
/// the lifetime of the backing buffer as opposed to that of the [`ZeroMap2dBorrowed`] instance.
///
/// # Examples
///
/// ```
/// use zerovec::maps::ZeroMap2dBorrowed;
///
/// // Example byte buffer representing the map { 1: {2: "three" } }
/// let BINCODE_BYTES: &[u8; 51] = &[
/// 2, 0, 0, 0, 0, 0, 0, 0, 1, 0, 4, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 2, 0,
/// 0, 0, 0, 0, 0, 0, 2, 0, 11, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 116,
/// 104, 114, 101, 101,
/// ];
///
/// // Deserializing to ZeroMap2d requires no heap allocations.
/// let zero_map: ZeroMap2dBorrowed<u16, u16, str> =
/// bincode::deserialize(BINCODE_BYTES)
/// .expect("Should deserialize successfully");
/// assert_eq!(zero_map.get_2d(&1, &2), Some("three"));
/// ```
///
/// This can be obtained from a [`ZeroMap2d`](super::ZeroMap2d) via [`ZeroMap2d::as_borrowed`](super::ZeroMap2d::as_borrowed)
pub struct ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
pub(crate) keys0: &'a K0::Slice,
pub(crate) joiner: &'a ZeroSlice<u32>,
pub(crate) keys1: &'a K1::Slice,
pub(crate) values: &'a V::Slice,
}
impl<'a, K0, K1, V> Copy for ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
}
impl<'a, K0, K1, V> Clone for ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
fn clone(&self) -> Self {
*self
}
}
impl<'a, K0, K1, V> Default for ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0::Slice: 'static,
K1::Slice: 'static,
V::Slice: 'static,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
fn default() -> Self {
Self::new()
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0::Slice: 'static,
K1::Slice: 'static,
V::Slice: 'static,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
/// Creates a new, empty `ZeroMap2dBorrowed<K0, K1, V>`.
///
/// Note: Since [`ZeroMap2dBorrowed`] is not mutable, the return value will be a stub unless
/// converted into a [`ZeroMap2d`](super::ZeroMap2d).
///
/// # Examples
///
/// ```
/// use zerovec::maps::ZeroMap2dBorrowed;
///
/// let zm: ZeroMap2dBorrowed<u16, u16, str> = ZeroMap2dBorrowed::new();
/// assert!(zm.is_empty());
/// ```
pub fn new() -> Self {
Self {
keys0: K0::Container::zvl_new_borrowed(),
joiner: Default::default(),
keys1: K1::Container::zvl_new_borrowed(),
values: V::Container::zvl_new_borrowed(),
}
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
#[doc(hidden)] // databake internal
pub const unsafe fn from_parts_unchecked(
keys0: &'a K0::Slice,
joiner: &'a ZeroSlice<u32>,
keys1: &'a K1::Slice,
values: &'a V::Slice,
) -> Self {
Self {
keys0,
joiner,
keys1,
values,
}
}
/// The number of elements in the [`ZeroMap2dBorrowed`]
pub fn len(&self) -> usize {
self.values.zvl_len()
}
/// Whether the [`ZeroMap2dBorrowed`] is empty
pub fn is_empty(&self) -> bool {
self.values.zvl_len() == 0
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a> + Ord,
K1: ZeroMapKV<'a> + Ord,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
/// Get the value associated with `key0` and `key1`, if it exists.
///
/// This is able to return values that live longer than the map itself
/// since they borrow directly from the backing buffer. This is the
/// primary advantage of using [`ZeroMap2dBorrowed`](super::ZeroMap2dBorrowed) over [`ZeroMap2d`](super::ZeroMap2d).
///
/// ```rust
/// use zerovec::ZeroMap2d;
///
/// let mut map = ZeroMap2d::new();
/// map.insert(&1, "one", "foo");
/// map.insert(&2, "one", "bar");
/// map.insert(&2, "two", "baz");
///
/// let borrowed = map.as_borrowed();
/// assert_eq!(borrowed.get_2d(&1, "one"), Some("foo"));
/// assert_eq!(borrowed.get_2d(&1, "two"), None);
/// assert_eq!(borrowed.get_2d(&2, "one"), Some("bar"));
/// assert_eq!(borrowed.get_2d(&2, "two"), Some("baz"));
/// assert_eq!(borrowed.get_2d(&3, "three"), None);
/// ```
pub fn get_2d(&self, key0: &K0, key1: &K1) -> Option<&'a V::GetType> {
self.get0(key0)?.get1(key1)
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a> + Ord,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
/// Gets a cursor for `key0`. If `None`, then `key0` is not in the map. If `Some`,
/// then `key0` is in the map, and `key1` can be queried.
///
/// ```rust
/// use zerovec::ZeroMap2d;
///
/// let mut map = ZeroMap2d::new();
/// map.insert(&1, "one", "foo");
/// map.insert(&2, "two", "bar");
/// let borrowed = map.as_borrowed();
/// assert!(matches!(borrowed.get0(&1), Some(_)));
/// assert!(matches!(borrowed.get0(&3), None));
/// ```
#[inline]
pub fn get0<'l>(&'l self, key0: &K0) -> Option<ZeroMap2dCursor<'a, 'a, K0, K1, V>> {
let key0_index = self.keys0.zvl_binary_search(key0).ok()?;
Some(ZeroMap2dCursor::from_borrowed(self, key0_index))
}
/// Binary search the map for `key0`, returning a cursor.
///
/// ```rust
/// use zerovec::ZeroMap2d;
///
/// let mut map = ZeroMap2d::new();
/// map.insert(&1, "one", "foo");
/// map.insert(&2, "two", "bar");
/// let borrowed = map.as_borrowed();
/// assert!(matches!(borrowed.get0_by(|probe| probe.cmp(&1)), Some(_)));
/// assert!(matches!(borrowed.get0_by(|probe| probe.cmp(&3)), None));
/// ```
pub fn get0_by<'l>(
&'l self,
predicate: impl FnMut(&K0) -> Ordering,
) -> Option<ZeroMap2dCursor<'a, 'a, K0, K1, V>> {
let key0_index = self.keys0.zvl_binary_search_by(predicate).ok()?;
Some(ZeroMap2dCursor::from_borrowed(self, key0_index))
}
/// Returns whether `key0` is contained in this map
///
/// ```rust
/// use zerovec::ZeroMap2d;
///
/// let mut map = ZeroMap2d::new();
/// map.insert(&1, "one", "foo");
/// map.insert(&2, "two", "bar");
/// let borrowed = map.as_borrowed();
/// assert!(borrowed.contains_key0(&1));
/// assert!(!borrowed.contains_key0(&3));
/// ```
pub fn contains_key0(&self, key0: &K0) -> bool {
self.keys0.zvl_binary_search(key0).is_ok()
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a>,
K1: ZeroMapKV<'a>,
V: ZeroMapKV<'a>,
K0: ?Sized,
K1: ?Sized,
V: ?Sized,
{
/// Produce an ordered iterator over keys0
pub fn iter0<'l>(&'l self) -> impl Iterator<Item = ZeroMap2dCursor<'a, 'a, K0, K1, V>> + '_ {
(0..self.keys0.zvl_len()).map(move |idx| ZeroMap2dCursor::from_borrowed(self, idx))
}
}
impl<'a, K0, K1, V> ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a> + Ord,
K1: ZeroMapKV<'a> + Ord,
V: ZeroMapKV<'a>,
V: Copy,
K0: ?Sized,
K1: ?Sized,
{
/// For cases when `V` is fixed-size, obtain a direct copy of `V` instead of `V::ULE`
pub fn get_copied_2d(&self, key0: &K0, key1: &K1) -> Option<V> {
self.get0(key0)?.get1_copied(key1)
}
}
// We can't use the default PartialEq because ZeroMap2d is invariant
// so otherwise rustc will not automatically allow you to compare ZeroMaps
// with different lifetimes
impl<'a, 'b, K0, K1, V> PartialEq<ZeroMap2dBorrowed<'b, K0, K1, V>>
for ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: for<'c> ZeroMapKV<'c> + ?Sized,
K1: for<'c> ZeroMapKV<'c> + ?Sized,
V: for<'c> ZeroMapKV<'c> + ?Sized,
<K0 as ZeroMapKV<'a>>::Slice: PartialEq<<K0 as ZeroMapKV<'b>>::Slice>,
<K1 as ZeroMapKV<'a>>::Slice: PartialEq<<K1 as ZeroMapKV<'b>>::Slice>,
<V as ZeroMapKV<'a>>::Slice: PartialEq<<V as ZeroMapKV<'b>>::Slice>,
{
fn eq(&self, other: &ZeroMap2dBorrowed<'b, K0, K1, V>) -> bool {
self.keys0.eq(other.keys0)
&& self.joiner.eq(other.joiner)
&& self.keys1.eq(other.keys1)
&& self.values.eq(other.values)
}
}
impl<'a, K0, K1, V> fmt::Debug for ZeroMap2dBorrowed<'a, K0, K1, V>
where
K0: ZeroMapKV<'a> + ?Sized,
K1: ZeroMapKV<'a> + ?Sized,
V: ZeroMapKV<'a> + ?Sized,
K0::Slice: fmt::Debug,
K1::Slice: fmt::Debug,
V::Slice: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
f.debug_struct("ZeroMap2dBorrowed")
.field("keys0", &self.keys0)
.field("joiner", &self.joiner)
.field("keys1", &self.keys1)
.field("values", &self.values)
.finish()
}
}