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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /vendor/indexmap/src/mutable_keys.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/indexmap/src/mutable_keys.rs')
-rw-r--r--vendor/indexmap/src/mutable_keys.rs75
1 files changed, 75 insertions, 0 deletions
diff --git a/vendor/indexmap/src/mutable_keys.rs b/vendor/indexmap/src/mutable_keys.rs
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+use core::hash::{BuildHasher, Hash};
+
+use super::{Equivalent, IndexMap};
+
+pub struct PrivateMarker {}
+
+/// Opt-in mutable access to keys.
+///
+/// These methods expose `&mut K`, mutable references to the key as it is stored
+/// in the map.
+/// You are allowed to modify the keys in the hashmap **if the modification
+/// does not change the key’s hash and equality**.
+///
+/// If keys are modified erroneously, you can no longer look them up.
+/// This is sound (memory safe) but a logical error hazard (just like
+/// implementing PartialEq, Eq, or Hash incorrectly would be).
+///
+/// `use` this trait to enable its methods for `IndexMap`.
+pub trait MutableKeys {
+ type Key;
+ type Value;
+
+ /// Return item index, mutable reference to key and value
+ fn get_full_mut2<Q: ?Sized>(
+ &mut self,
+ key: &Q,
+ ) -> Option<(usize, &mut Self::Key, &mut Self::Value)>
+ where
+ Q: Hash + Equivalent<Self::Key>;
+
+ /// Scan through each key-value pair in the map and keep those where the
+ /// closure `keep` returns `true`.
+ ///
+ /// The elements are visited in order, and remaining elements keep their
+ /// order.
+ ///
+ /// Computes in **O(n)** time (average).
+ fn retain2<F>(&mut self, keep: F)
+ where
+ F: FnMut(&mut Self::Key, &mut Self::Value) -> bool;
+
+ /// This method is not useful in itself – it is there to “seal” the trait
+ /// for external implementation, so that we can add methods without
+ /// causing breaking changes.
+ fn __private_marker(&self) -> PrivateMarker;
+}
+
+/// Opt-in mutable access to keys.
+///
+/// See [`MutableKeys`](trait.MutableKeys.html) for more information.
+impl<K, V, S> MutableKeys for IndexMap<K, V, S>
+where
+ K: Eq + Hash,
+ S: BuildHasher,
+{
+ type Key = K;
+ type Value = V;
+ fn get_full_mut2<Q: ?Sized>(&mut self, key: &Q) -> Option<(usize, &mut K, &mut V)>
+ where
+ Q: Hash + Equivalent<K>,
+ {
+ self.get_full_mut2_impl(key)
+ }
+
+ fn retain2<F>(&mut self, keep: F)
+ where
+ F: FnMut(&mut K, &mut V) -> bool,
+ {
+ self.retain_mut(keep)
+ }
+
+ fn __private_marker(&self) -> PrivateMarker {
+ PrivateMarker {}
+ }
+}