X-Git-Url: https://git.chrismorgan.info/anymap/blobdiff_plain/18518214c4609e182be5277b14c7c510c8fa9505..fdba2f45b9b9d6fa05be6a4d0849add42d94516e:/src/raw/mod.rs

diff --git a/src/raw/mod.rs b/src/raw/mod.rs
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+//! The raw form of an AnyMap, allowing untyped access.
+//!
+//! All relevant details are in the `RawAnyMap` struct.
+
+use std::any::TypeId;
+use std::borrow::Borrow;
+use std::collections::hash_map::{self, HashMap};
+#[cfg(feature = "nightly")]
+use std::collections::hash_state::HashState;
+use std::default::Default;
+use std::hash::Hash;
+#[cfg(feature = "nightly")]
+use std::hash::Hasher;
+use std::iter::IntoIterator;
+#[cfg(feature = "nightly")]
+use std::mem;
+use std::ops::{Index, IndexMut};
+#[cfg(feature = "nightly")]
+use std::ptr;
+
+pub use self::any::Any;
+
+mod any;
+
+#[cfg(feature = "nightly")]
+struct TypeIdHasher {
+    value: u64,
+}
+
+#[cfg_attr(feature = "clone", derive(Clone))]
+#[cfg(feature = "nightly")]
+struct TypeIdState;
+
+#[cfg(feature = "nightly")]
+impl HashState for TypeIdState {
+    type Hasher = TypeIdHasher;
+
+    fn hasher(&self) -> TypeIdHasher {
+        TypeIdHasher { value: 0 }
+    }
+}
+
+#[cfg(feature = "nightly")]
+impl Hasher for TypeIdHasher {
+    #[inline(always)]
+    fn write(&mut self, bytes: &[u8]) {
+        // This expects to receive one and exactly one 64-bit value
+        debug_assert!(bytes.len() == 8);
+        unsafe {
+            ptr::copy_nonoverlapping(&mut self.value, mem::transmute(&bytes[0]), 1)
+        }
+    }
+
+    #[inline(always)]
+    fn finish(&self) -> u64 { self.value }
+}
+
+
+/// The raw, underlying form of an AnyMap.
+///
+/// At its essence, this is a wrapper around `HashMap<TypeId, Box<Any>>`, with the portions that
+/// would be memory-unsafe removed or marked unsafe. Normal people are expected to use the safe
+/// `AnyMap` interface instead, but there is the occasional use for this such as iteration over the
+/// contents of an `AnyMap`. However, because you will then be dealing with `Any` trait objects, it
+/// doesn’t tend to be so very useful. Still, if you need it, it’s here.
+#[derive(Debug)]
+#[cfg_attr(feature = "clone", derive(Clone))]
+pub struct RawAnyMap {
+    #[cfg(feature = "nightly")]
+    inner: HashMap<TypeId, Box<Any>, TypeIdState>,
+
+    #[cfg(not(feature = "nightly"))]
+    inner: HashMap<TypeId, Box<Any>>,
+}
+
+impl Default for RawAnyMap {
+    fn default() -> RawAnyMap {
+        RawAnyMap::new()
+    }
+}
+
+#[cfg(feature = "nightly")]
+impl_common_methods! {
+    field: RawAnyMap.inner;
+    new() => HashMap::with_hash_state(TypeIdState);
+    with_capacity(capacity) => HashMap::with_capacity_and_hash_state(capacity, TypeIdState);
+}
+
+#[cfg(not(feature = "nightly"))]
+impl_common_methods! {
+    field: RawAnyMap.inner;
+    new() => HashMap::new();
+    with_capacity(capacity) => HashMap::with_capacity(capacity);
+}
+
+/// RawAnyMap iterator.
+#[derive(Clone)]
+pub struct Iter<'a> {
+    inner: hash_map::Iter<'a, TypeId, Box<Any>>,
+}
+impl<'a> Iterator for Iter<'a> {
+    type Item = &'a Any;
+    #[inline] fn next(&mut self) -> Option<&'a Any> { self.inner.next().map(|x| &**x.1) }
+    #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl<'a> ExactSizeIterator for Iter<'a> {
+    #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap mutable iterator.
+pub struct IterMut<'a> {
+    inner: hash_map::IterMut<'a, TypeId, Box<Any>>,
+}
+impl<'a> Iterator for IterMut<'a> {
+    type Item = &'a mut Any;
+    #[inline] fn next(&mut self) -> Option<&'a mut Any> { self.inner.next().map(|x| &mut **x.1) }
+    #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl<'a> ExactSizeIterator for IterMut<'a> {
+    #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap move iterator.
+pub struct IntoIter {
+    inner: hash_map::IntoIter<TypeId, Box<Any>>,
+}
+impl Iterator for IntoIter {
+    type Item = Box<Any>;
+    #[inline] fn next(&mut self) -> Option<Box<Any>> { self.inner.next().map(|x| x.1) }
+    #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+impl ExactSizeIterator for IntoIter {
+    #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+/// RawAnyMap drain iterator.
+#[cfg(feature = "nightly")]
+pub struct Drain<'a> {
+    inner: hash_map::Drain<'a, TypeId, Box<Any>>,
+}
+#[cfg(feature = "nightly")]
+impl<'a> Iterator for Drain<'a> {
+    type Item = Box<Any>;
+    #[inline] fn next(&mut self) -> Option<Box<Any>> { self.inner.next().map(|x| x.1) }
+    #[inline] fn size_hint(&self) -> (usize, Option<usize>) { self.inner.size_hint() }
+}
+#[cfg(feature = "nightly")]
+impl<'a> ExactSizeIterator for Drain<'a> {
+    #[inline] fn len(&self) -> usize { self.inner.len() }
+}
+
+impl RawAnyMap {
+    /// An iterator visiting all entries in arbitrary order.
+    ///
+    /// Iterator element type is `&Any`.
+    #[inline]
+    pub fn iter(&self) -> Iter {
+        Iter {
+            inner: self.inner.iter(),
+        }
+    }
+
+    /// An iterator visiting all entries in arbitrary order.
+    ///
+    /// Iterator element type is `&mut Any`.
+    #[inline]
+    pub fn iter_mut(&mut self) -> IterMut {
+        IterMut {
+            inner: self.inner.iter_mut(),
+        }
+    }
+
+    /// Creates a consuming iterator, that is, one that moves each item
+    /// out of the map in arbitrary order. The map cannot be used after
+    /// calling this.
+    ///
+    /// Iterator element type is `Box<Any>`.
+    #[inline]
+    pub fn into_iter(self) -> IntoIter {
+        IntoIter {
+            inner: self.inner.into_iter(),
+        }
+    }
+
+    /// Clears the map, returning all items as an iterator.
+    ///
+    /// Iterator element type is `Box<Any>`.
+    ///
+    /// Keeps the allocated memory for reuse.
+    #[inline]
+    #[cfg(feature = "nightly")]
+    pub fn drain(&mut self) -> Drain {
+        Drain {
+            inner: self.inner.drain(),
+        }
+    }
+
+    /// Gets the entry for the given type in the collection for in-place manipulation.
+    pub fn entry(&mut self, key: TypeId) -> Entry {
+        match self.inner.entry(key) {
+            hash_map::Entry::Occupied(e) => Entry::Occupied(OccupiedEntry {
+                inner: e,
+            }),
+            hash_map::Entry::Vacant(e) => Entry::Vacant(VacantEntry {
+                inner: e,
+            }),
+        }
+    }
+
+    /// Returns a reference to the value corresponding to the key.
+    ///
+    /// The key may be any borrowed form of the map's key type, but `Hash` and `Eq` on the borrowed
+    /// form *must* match those for the key type.
+    pub fn get<Q: ?Sized>(&self, k: &Q) -> Option<&Any>
+    where TypeId: Borrow<Q>, Q: Hash + Eq {
+        self.inner.get(k).map(|x| &**x)
+    }
+
+    /// 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 `Hash` and `Eq` on the borrowed
+    /// form *must* match those for the key type.
+    pub fn contains_key<Q: ?Sized>(&self, k: &Q) -> bool
+    where TypeId: Borrow<Q>, Q: Hash + Eq {
+        self.inner.contains_key(k)
+    }
+
+    /// 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 `Hash` and `Eq` on the borrowed
+    /// form *must* match those for the key type.
+    pub fn get_mut<Q: ?Sized>(&mut self, k: &Q) -> Option<&mut Any>
+    where TypeId: Borrow<Q>, Q: Hash + Eq {
+        self.inner.get_mut(k).map(|x| &mut **x)
+    }
+
+    /// Inserts a key-value pair from the map. If the key already had a value present in the map,
+    /// that value is returned. Otherwise, None is returned.
+    ///
+    /// It is the caller’s responsibility to ensure that the key corresponds with the type ID of
+    /// the value. If they do not, memory safety may be violated.
+    pub unsafe fn insert(&mut self, key: TypeId, value: Box<Any>) -> Option<Box<Any>> {
+        self.inner.insert(key, value)
+    }
+
+    /// 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 `Hash` and `Eq` on the borrowed
+    /// form *must* match those for the key type.
+    pub fn remove<Q: ?Sized>(&mut self, k: &Q) -> Option<Box<Any>>
+    where TypeId: Borrow<Q>, Q: Hash + Eq {
+        self.inner.remove(k)
+    }
+
+}
+
+impl<Q> Index<Q> for RawAnyMap where TypeId: Borrow<Q>, Q: Eq + Hash {
+    type Output = Any;
+
+    fn index<'a>(&'a self, index: Q) -> &'a Any {
+        self.get(&index).expect("no entry found for key")
+    }
+}
+
+impl<Q> IndexMut<Q> for RawAnyMap where TypeId: Borrow<Q>, Q: Eq + Hash {
+    fn index_mut<'a>(&'a mut self, index: Q) -> &'a mut Any {
+        self.get_mut(&index).expect("no entry found for key")
+    }
+}
+
+impl IntoIterator for RawAnyMap {
+    type Item = Box<Any>;
+    type IntoIter = IntoIter;
+
+    fn into_iter(self) -> IntoIter {
+        self.into_iter()
+    }
+}
+
+/// A view into a single occupied location in a `RawAnyMap`.
+pub struct OccupiedEntry<'a> {
+    inner: hash_map::OccupiedEntry<'a, TypeId, Box<Any>>,
+}
+
+/// A view into a single empty location in a `RawAnyMap`.
+pub struct VacantEntry<'a> {
+    inner: hash_map::VacantEntry<'a, TypeId, Box<Any>>,
+}
+
+/// A view into a single location in an AnyMap, which may be vacant or occupied.
+pub enum Entry<'a> {
+    /// An occupied Entry
+    Occupied(OccupiedEntry<'a>),
+    /// A vacant Entry
+    Vacant(VacantEntry<'a>),
+}
+
+impl<'a> Entry<'a> {
+    /// Ensures a value is in the entry by inserting the default if empty, and returns
+    /// a mutable reference to the value in the entry.
+    ///
+    /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+    /// the type ID of `value`. If they do not, memory safety may be violated.
+    pub unsafe fn or_insert(self, default: Box<Any>) -> &'a mut Any {
+        match self {
+            Entry::Occupied(inner) => inner.into_mut(),
+            Entry::Vacant(inner) => inner.insert(default),
+        }
+    }
+
+    /// 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.
+    ///
+    /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+    /// the type ID of `value`. If they do not, memory safety may be violated.
+    pub unsafe fn or_insert_with<F: FnOnce() -> Box<Any>>(self, default: F) -> &'a mut Any {
+        match self {
+            Entry::Occupied(inner) => inner.into_mut(),
+            Entry::Vacant(inner) => inner.insert(default()),
+        }
+    }
+}
+
+impl<'a> OccupiedEntry<'a> {
+    /// Gets a reference to the value in the entry.
+    pub fn get(&self) -> &Any {
+        &**self.inner.get() 
+    }
+
+    /// Gets a mutable reference to the value in the entry.
+    pub fn get_mut(&mut self) -> &mut Any {
+        &mut **self.inner.get_mut()
+    }
+
+    /// Converts the OccupiedEntry into a mutable reference to the value in the entry
+    /// with a lifetime bound to the collection itself.
+    pub fn into_mut(self) -> &'a mut Any {
+        &mut **self.inner.into_mut()
+    }
+
+    /// Sets the value of the entry, and returns the entry's old value.
+    ///
+    /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+    /// the type ID of `value`. If they do not, memory safety may be violated.
+    pub unsafe fn insert(&mut self, value: Box<Any>) -> Box<Any> {
+        self.inner.insert(value)
+    }
+
+    /// Takes the value out of the entry, and returns it.
+    pub fn remove(self) -> Box<Any> {
+        self.inner.remove()
+    }
+}
+
+impl<'a> VacantEntry<'a> {
+    /// Sets the value of the entry with the VacantEntry's key,
+    /// and returns a mutable reference to it
+    ///
+    /// It is the caller’s responsibility to ensure that the key of the entry corresponds with
+    /// the type ID of `value`. If they do not, memory safety may be violated.
+    pub unsafe fn insert(self, value: Box<Any>) -> &'a mut Any {
+        &mut **self.inner.insert(value)
+    }
+}