Trait in_place::entry::KeyMutableOccupiedEntry

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pub trait KeyMutableOccupiedEntry<'c>: KeyedOccupiedEntry<'c> {
    fn replace_key<'e>(
        &'e mut self, 
        key: Self::Key
    ) -> Result<Self::Key, Self::Key>;
}

Expand description

A trait to extend OccupiedEntry, allowing the user to mutate keys.

They are only able to do so through a replace_key function, not a regular mutable reference, so the implementer can ensure that collection invariants still hold for the new key.

Required methods

source

fn replace_key<'e>(&'e mut self, key: Self::Key) -> Result<Self::Key, Self::Key>

replace key with another one.

the data structure’s integrity is maintained. If the value would move in the collection (for example if the key changed hash in a hashmap) then the error state is returned, with the new_key not inserted.

Trait in_place::entry::KeyMutableOccupiedEntry

Required methods

fn replace_key<'e>(&'e mut self, key: Self::Key) -> Result<Self::Key, Self::Key>

Implementors