use iter::{self, Iterator, ExactSizeIterator, IntoIterator, IteratorExt, FromIterator, Extend, Map};
use marker::Sized;
use mem::{self, replace};
-use num::{Int, UnsignedInt};
-use ops::{Deref, FnMut, Index, IndexMut};
+use ops::{Deref, FnMut, Index};
use option::Option::{self, Some, None};
use rand::{self, Rng};
use result::Result::{self, Ok, Err};
/// It is required that the keys implement the `Eq` and `Hash` traits, although
/// this can frequently be achieved by using `#[derive(Eq, Hash)]`.
///
+/// It is a logic error for a key to be modified in such a way that the key's
+/// hash, as determined by the `Hash` trait, or its equality, as determined by
+/// the `Eq` trait, changes while it is in the map. This is normally only
+/// possible through `Cell`, `RefCell`, global state, I/O, or unsafe code.
+///
/// Relevant papers/articles:
///
/// 1. Pedro Celis. ["Robin Hood Hashing"](https://cs.uwaterloo.ca/research/tr/1986/CS-86-14.pdf)
}
}
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<K, V, S, Q: ?Sized> IndexMut<Q> for HashMap<K, V, S>
- where K: Eq + Hash + Borrow<Q>,
- Q: Eq + Hash,
- S: HashState,
-{
- #[inline]
- fn index_mut<'a>(&'a mut self, index: &Q) -> &'a mut V {
- self.get_mut(index).expect("no entry found for key")
- }
-}
-
/// HashMap iterator.
#[stable(feature = "rust1", since = "1.0.0")]
pub struct Iter<'a, K: 'a, V: 'a> {