Enum Entry 

pub enum Entry<'a, K: Key + 'static, V: Value + 'static> {
    Occupied(OccupiedEntry<'a, K, V>),
    Vacant(VacantEntry<'a, K, V>),
}

A view into a single entry in a Table, which may either be vacant or occupied.

This enum is constructed from the entry method on Table, and mirrors std::collections::btree_map::Entry as closely as the redb data model allows.

Unlike the in-memory BTreeMap, redb values are stored serialized, so methods that produce a “reference to the value” return an AccessGuardMut instead of &mut V.

Variants

Occupied(OccupiedEntry<'a, K, V>)

An occupied entry.

Vacant(VacantEntry<'a, K, V>)

A vacant entry.

Implementations

impl<'a, K: Key + 'static, V: Value + 'static> Entry<'a, K, V>

pub fn key(&self) -> &K::SelfType<'a>

Returns a view of this entry’s key.

pub fn or_insert<'v>( self, default: impl Borrow<V::SelfType<'v>>, ) -> Result<AccessGuardMut<'a, V>>

Ensures a value is in the entry by inserting the provided default if empty, and returns a mutable accessor to the value in the entry.

pub fn or_insert_with<'v, F, B>( self, default: F, ) -> Result<AccessGuardMut<'a, V>>

where F: FnOnce() -> B, B: Borrow<V::SelfType<'v>>,

Ensures a value is in the entry by inserting the result of default if empty, and returns a mutable accessor to the value in the entry.

Unlike or_insert, the default value is only computed if the entry is vacant.

pub fn or_insert_with_key<'v, F, B>( self, default: F, ) -> Result<AccessGuardMut<'a, V>>

where F: FnOnce(&K::SelfType<'a>) -> B, B: Borrow<V::SelfType<'v>>,

Ensures a value is in the entry by inserting, if empty, the result of the default function, which is given a view of the key.

pub fn and_modify<F>(self, f: F) -> Result<Self>

where F: FnOnce(&mut AccessGuardMut<'_, V>) -> Result<()>,

Provides in-place mutable access to an occupied entry before any potential inserts into the table.

The closure receives an AccessGuardMut and may replace the stored value via AccessGuardMut::insert. Any errors returned by the closure are propagated.