Struct rusty_leveldb::DBIterator

pub struct DBIterator { /* fields omitted */ }

DBIterator is an iterator over the contents of a database.

Methods

impl DBIterator

pub fn new(
    cmp: Rc<Box<dyn Cmp>>,
    vset: Rc<RefCell<VersionSet>>,
    iter: MergingIter,
    ss: Snapshot
) -> DBIterator

Trait Implementations

impl LdbIterator for DBIterator

fn advance(&mut self) -> bool

Advances the position of the iterator by one element (which can be retrieved using current(). If no more elements are available, advance() returns false, and the iterator becomes invalid (i.e. as if reset() had been called).

fn current(&self, key: &mut Vec<u8>, val: &mut Vec<u8>) -> bool

Return the current item (i.e. the item most recently returned by next()).

fn prev(&mut self) -> bool

Go to the previous item; if the iterator is moved beyond the first element, prev() returns false and it will be !valid(). This is inefficient for most iterator implementations.

fn valid(&self) -> bool

Returns true if the iterator is not positioned before the first or after the last element, i.e. if current() would succeed.

fn seek(&mut self, to: &[u8])

Seek the iterator to key or the next bigger key. If the seek is invalid (past last element, or before first element), the iterator is reset() and not valid.

fn seek_to_first(&mut self)

seek_to_first seeks to the first element.

fn reset(&mut self)

Resets the iterator to be !valid(), i.e. positioned before the first element.

fn next(&mut self) -> Option<(Vec<u8>, Vec<u8>)>

next is like Iterator::next(). It's implemented here because Rust disallows implementing a foreign trait for any type, thus we can't do impl<T: LdbIterator> Iterator<Item=Vec<u8>> for T {}.