X-Git-Url: https://git.chrismorgan.info/anymap/blobdiff_plain/b549457d628fb178f6d700d85800f3ab63482d63..27eca551823bac40421ae7ee6e83e7541790b723:/src/raw.rs diff --git a/src/raw.rs b/src/raw.rs deleted file mode 100644 index 7d53783..0000000 --- a/src/raw.rs +++ /dev/null @@ -1,357 +0,0 @@ -//! The raw form of a `Map`, allowing untyped access. -//! -//! All relevant details are in the `RawMap` struct. - -use std::any::TypeId; -use std::borrow::Borrow; -use std::collections::hash_map::{self, HashMap}; -use std::hash::Hash; -use std::hash::{Hasher, BuildHasherDefault}; -use std::mem; -use std::ops::{Index, IndexMut}; -use std::ptr; - -use any::{Any, UncheckedAnyExt}; - -#[derive(Default)] -struct TypeIdHasher { - value: u64, -} - -impl Hasher for TypeIdHasher { - #[inline] - 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(mem::transmute(&bytes[0]), &mut self.value, 1) - } - } - - #[inline] - fn finish(&self) -> u64 { self.value } -} - -#[test] -fn type_id_hasher() { - fn verify_hashing_with(type_id: TypeId) { - let mut hasher = TypeIdHasher::default(); - type_id.hash(&mut hasher); - assert_eq!(hasher.finish(), unsafe { mem::transmute::(type_id) }); - } - // Pick a variety of types, just to demonstrate it’s all sane. Normal, zero-sized, unsized, &c. - verify_hashing_with(TypeId::of::()); - verify_hashing_with(TypeId::of::<()>()); - verify_hashing_with(TypeId::of::()); - verify_hashing_with(TypeId::of::<&str>()); - verify_hashing_with(TypeId::of::>()); -} - -/// The raw, underlying form of a `Map`. -/// -/// At its essence, this is a wrapper around `HashMap>`, with the portions that -/// would be memory-unsafe removed or marked unsafe. Normal people are expected to use the safe -/// `Map` interface instead, but there is the occasional use for this such as iteration over the -/// contents of an `Map`. 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)] -pub struct RawMap { - inner: HashMap, BuildHasherDefault>, -} - -// #[derive(Clone)] would want A to implement Clone, but in reality it’s only Box that can. -impl Clone for RawMap where Box: Clone { - #[inline] - fn clone(&self) -> RawMap { - RawMap { - inner: self.inner.clone(), - } - } -} - -impl Default for RawMap { - #[inline] - fn default() -> RawMap { - RawMap::new() - } -} - -impl_common_methods! { - field: RawMap.inner; - new() => HashMap::with_hasher(Default::default()); - with_capacity(capacity) => HashMap::with_capacity_and_hasher(capacity, Default::default()); -} - -/// `RawMap` iterator. -#[derive(Clone)] -pub struct Iter<'a, A: ?Sized + UncheckedAnyExt> { - inner: hash_map::Iter<'a, TypeId, Box>, -} -impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for Iter<'a, A> { - type Item = &'a A; - #[inline] fn next(&mut self) -> Option<&'a A> { self.inner.next().map(|x| &**x.1) } - #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } -} -impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for Iter<'a, A> { - #[inline] fn len(&self) -> usize { self.inner.len() } -} - -/// `RawMap` mutable iterator. -pub struct IterMut<'a, A: ?Sized + UncheckedAnyExt> { - inner: hash_map::IterMut<'a, TypeId, Box>, -} -impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for IterMut<'a, A> { - type Item = &'a mut A; - #[inline] fn next(&mut self) -> Option<&'a mut A> { self.inner.next().map(|x| &mut **x.1) } - #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } -} -impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for IterMut<'a, A> { - #[inline] fn len(&self) -> usize { self.inner.len() } -} - -/// `RawMap` move iterator. -pub struct IntoIter { - inner: hash_map::IntoIter>, -} -impl Iterator for IntoIter { - type Item = Box; - #[inline] fn next(&mut self) -> Option> { self.inner.next().map(|x| x.1) } - #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } -} -impl ExactSizeIterator for IntoIter { - #[inline] fn len(&self) -> usize { self.inner.len() } -} - -/// `RawMap` drain iterator. -pub struct Drain<'a, A: ?Sized + UncheckedAnyExt> { - inner: hash_map::Drain<'a, TypeId, Box>, -} -impl<'a, A: ?Sized + UncheckedAnyExt> Iterator for Drain<'a, A> { - type Item = Box; - #[inline] fn next(&mut self) -> Option> { self.inner.next().map(|x| x.1) } - #[inline] fn size_hint(&self) -> (usize, Option) { self.inner.size_hint() } -} -impl<'a, A: ?Sized + UncheckedAnyExt> ExactSizeIterator for Drain<'a, A> { - #[inline] fn len(&self) -> usize { self.inner.len() } -} - -impl RawMap { - /// 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(), - } - } - - /// Clears the map, returning all items as an iterator. - /// - /// Iterator element type is `Box`. - /// - /// Keeps the allocated memory for reuse. - #[inline] - 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. - #[inline] - 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. - #[inline] - pub fn get(&self, k: &Q) -> Option<&A> - where TypeId: Borrow, 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. - #[inline] - pub fn contains_key(&self, k: &Q) -> bool - where TypeId: Borrow, 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. - #[inline] - pub fn get_mut(&mut self, k: &Q) -> Option<&mut A> - where TypeId: Borrow, 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. - #[inline] - pub unsafe fn insert(&mut self, key: TypeId, value: Box) -> Option> { - 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. - #[inline] - pub fn remove(&mut self, k: &Q) -> Option> - where TypeId: Borrow, Q: Hash + Eq { - self.inner.remove(k) - } - -} - -impl Index for RawMap where TypeId: Borrow, Q: Eq + Hash { - type Output = A; - - #[inline] - fn index(&self, index: Q) -> &A { - self.get(&index).expect("no entry found for key") - } -} - -impl IndexMut for RawMap where TypeId: Borrow, Q: Eq + Hash { - #[inline] - fn index_mut(&mut self, index: Q) -> &mut A { - self.get_mut(&index).expect("no entry found for key") - } -} - -impl IntoIterator for RawMap { - type Item = Box; - type IntoIter = IntoIter; - - #[inline] - fn into_iter(self) -> IntoIter { - IntoIter { - inner: self.inner.into_iter(), - } - } -} - -/// A view into a single occupied location in a `RawMap`. -pub struct OccupiedEntry<'a, A: ?Sized + UncheckedAnyExt> { - inner: hash_map::OccupiedEntry<'a, TypeId, Box>, -} - -/// A view into a single empty location in a `RawMap`. -pub struct VacantEntry<'a, A: ?Sized + UncheckedAnyExt> { - inner: hash_map::VacantEntry<'a, TypeId, Box>, -} - -/// A view into a single location in a `RawMap`, which may be vacant or occupied. -pub enum Entry<'a, A: ?Sized + UncheckedAnyExt> { - /// An occupied Entry - Occupied(OccupiedEntry<'a, A>), - /// A vacant Entry - Vacant(VacantEntry<'a, A>), -} - -impl<'a, A: ?Sized + UncheckedAnyExt> Entry<'a, 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. - #[inline] - pub unsafe fn or_insert(self, default: Box) -> &'a mut A { - 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. - #[inline] - pub unsafe fn or_insert_with Box>(self, default: F) -> &'a mut A { - match self { - Entry::Occupied(inner) => inner.into_mut(), - Entry::Vacant(inner) => inner.insert(default()), - } - } -} - -impl<'a, A: ?Sized + UncheckedAnyExt> OccupiedEntry<'a, A> { - /// Gets a reference to the value in the entry. - #[inline] - pub fn get(&self) -> &A { - &**self.inner.get() - } - - /// Gets a mutable reference to the value in the entry. - #[inline] - pub fn get_mut(&mut self) -> &mut A { - &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. - #[inline] - pub fn into_mut(self) -> &'a mut A { - &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. - #[inline] - pub unsafe fn insert(&mut self, value: Box) -> Box { - self.inner.insert(value) - } - - /// Takes the value out of the entry, and returns it. - #[inline] - pub fn remove(self) -> Box { - self.inner.remove() - } -} - -impl<'a, A: ?Sized + UncheckedAnyExt> VacantEntry<'a, 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. - #[inline] - pub unsafe fn insert(self, value: Box) -> &'a mut A { - &mut **self.inner.insert(value) - } -}