pub enum IterDup<'txn> {
Err(Error),
Ok {
cursor: *mut MDB_cursor,
op: c_uint,
_marker: PhantomData<fn(&'txn ())>,
},
}
Expand description
An iterator over the keys and duplicate values in an LMDB database.
The yielded items of the iterator are themselves iterators over the duplicate values for a specific key.
Variants§
Err(Error)
An iterator that returns an error on every call to Iter.next(). Cursor.iter*() creates an Iter of this type when LMDB returns an error on retrieval of a cursor. Using this variant instead of returning an error makes Cursor.iter()* methods infallible, so consumers only need to check the result of Iter.next().
Ok
An iterator that returns an Item on calls to Iter.next(). The Item is a Result<(&’txn u8, &’txn u8)>, so this variant might still return an error, if retrieval of the key/value pair fails for some reason.
Fields
cursor: *mut MDB_cursor
The LMDB cursor with which to iterate.
_marker: PhantomData<fn(&'txn ())>
A marker to ensure the iterator doesn’t outlive the transaction.
Trait Implementations§
Source§impl<'txn> Iterator for IterDup<'txn>
impl<'txn> Iterator for IterDup<'txn>
Source§fn next(&mut self) -> Option<Iter<'txn>>
fn next(&mut self) -> Option<Iter<'txn>>
Source§fn next_chunk<const N: usize>(
&mut self,
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
fn next_chunk<const N: usize>(
&mut self,
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
Self: Sized,
iter_next_chunk
)N
values. Read more1.0.0 · Source§fn size_hint(&self) -> (usize, Option<usize>)
fn size_hint(&self) -> (usize, Option<usize>)
1.0.0 · Source§fn count(self) -> usizewhere
Self: Sized,
fn count(self) -> usizewhere
Self: Sized,
1.0.0 · Source§fn last(self) -> Option<Self::Item>where
Self: Sized,
fn last(self) -> Option<Self::Item>where
Self: Sized,
Source§fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>
iter_advance_by
)n
elements. Read more1.0.0 · Source§fn nth(&mut self, n: usize) -> Option<Self::Item>
fn nth(&mut self, n: usize) -> Option<Self::Item>
n
th element of the iterator. Read more1.28.0 · Source§fn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
fn step_by(self, step: usize) -> StepBy<Self>where
Self: Sized,
1.0.0 · Source§fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>
fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>
1.0.0 · Source§fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
Self: Sized,
U: IntoIterator,
fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
Self: Sized,
U: IntoIterator,
Source§fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>
fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>
iter_intersperse
)separator
between adjacent items of the original iterator. Read more1.0.0 · Source§fn map<B, F>(self, f: F) -> Map<Self, F>
fn map<B, F>(self, f: F) -> Map<Self, F>
1.0.0 · Source§fn filter<P>(self, predicate: P) -> Filter<Self, P>
fn filter<P>(self, predicate: P) -> Filter<Self, P>
1.0.0 · Source§fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>
1.0.0 · Source§fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
fn enumerate(self) -> Enumerate<Self>where
Self: Sized,
1.0.0 · Source§fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>
1.0.0 · Source§fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>
1.57.0 · Source§fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>
1.0.0 · Source§fn skip(self, n: usize) -> Skip<Self>where
Self: Sized,
fn skip(self, n: usize) -> Skip<Self>where
Self: Sized,
n
elements. Read more1.0.0 · Source§fn take(self, n: usize) -> Take<Self>where
Self: Sized,
fn take(self, n: usize) -> Take<Self>where
Self: Sized,
n
elements, or fewer
if the underlying iterator ends sooner. Read more1.0.0 · Source§fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>
1.29.0 · Source§fn flatten(self) -> Flatten<Self>
fn flatten(self) -> Flatten<Self>
Source§fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>
fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>
iter_map_windows
)f
for each contiguous window of size N
over
self
and returns an iterator over the outputs of f
. Like slice::windows()
,
the windows during mapping overlap as well. Read more1.0.0 · Source§fn inspect<F>(self, f: F) -> Inspect<Self, F>
fn inspect<F>(self, f: F) -> Inspect<Self, F>
1.0.0 · Source§fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
fn by_ref(&mut self) -> &mut Selfwhere
Self: Sized,
Source§fn collect_into<E>(self, collection: &mut E) -> &mut E
fn collect_into<E>(self, collection: &mut E) -> &mut E
iter_collect_into
)1.0.0 · Source§fn partition<B, F>(self, f: F) -> (B, B)
fn partition<B, F>(self, f: F) -> (B, B)
Source§fn is_partitioned<P>(self, predicate: P) -> bool
fn is_partitioned<P>(self, predicate: P) -> bool
iter_is_partitioned
)true
precede all those that return false
. Read more1.27.0 · Source§fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R
1.27.0 · Source§fn try_for_each<F, R>(&mut self, f: F) -> R
fn try_for_each<F, R>(&mut self, f: F) -> R
1.0.0 · Source§fn fold<B, F>(self, init: B, f: F) -> B
fn fold<B, F>(self, init: B, f: F) -> B
1.51.0 · Source§fn reduce<F>(self, f: F) -> Option<Self::Item>
fn reduce<F>(self, f: F) -> Option<Self::Item>
Source§fn try_reduce<R>(
&mut self,
f: impl FnMut(Self::Item, Self::Item) -> R,
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
fn try_reduce<R>( &mut self, f: impl FnMut(Self::Item, Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType
iterator_try_reduce
)1.0.0 · Source§fn all<F>(&mut self, f: F) -> bool
fn all<F>(&mut self, f: F) -> bool
1.0.0 · Source§fn any<F>(&mut self, f: F) -> bool
fn any<F>(&mut self, f: F) -> bool
1.0.0 · Source§fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
fn find<P>(&mut self, predicate: P) -> Option<Self::Item>
1.30.0 · Source§fn find_map<B, F>(&mut self, f: F) -> Option<B>
fn find_map<B, F>(&mut self, f: F) -> Option<B>
Source§fn try_find<R>(
&mut self,
f: impl FnMut(&Self::Item) -> R,
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
fn try_find<R>( &mut self, f: impl FnMut(&Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType
try_find
)1.0.0 · Source§fn position<P>(&mut self, predicate: P) -> Option<usize>
fn position<P>(&mut self, predicate: P) -> Option<usize>
1.6.0 · Source§fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 · Source§fn max_by<F>(self, compare: F) -> Option<Self::Item>
fn max_by<F>(self, compare: F) -> Option<Self::Item>
1.6.0 · Source§fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>
1.15.0 · Source§fn min_by<F>(self, compare: F) -> Option<Self::Item>
fn min_by<F>(self, compare: F) -> Option<Self::Item>
1.0.0 · Source§fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)
1.36.0 · Source§fn copied<'a, T>(self) -> Copied<Self>
fn copied<'a, T>(self) -> Copied<Self>
Source§fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
Self: Sized,
fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
Self: Sized,
iter_array_chunks
)N
elements of the iterator at a time. Read more1.11.0 · Source§fn product<P>(self) -> P
fn product<P>(self) -> P
Source§fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering
iter_order_by
)Iterator
with those
of another with respect to the specified comparison function. Read more1.5.0 · Source§fn partial_cmp<I>(self, other: I) -> Option<Ordering>
fn partial_cmp<I>(self, other: I) -> Option<Ordering>
PartialOrd
elements of
this Iterator
with those of another. The comparison works like short-circuit
evaluation, returning a result without comparing the remaining elements.
As soon as an order can be determined, the evaluation stops and a result is returned. Read moreSource§fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>where
Self: Sized,
I: IntoIterator,
F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,
iter_order_by
)Iterator
with those
of another with respect to the specified comparison function. Read moreSource§fn eq_by<I, F>(self, other: I, eq: F) -> bool
fn eq_by<I, F>(self, other: I, eq: F) -> bool
iter_order_by
)1.5.0 · Source§fn lt<I>(self, other: I) -> bool
fn lt<I>(self, other: I) -> bool
Iterator
are lexicographically
less than those of another. Read more1.5.0 · Source§fn le<I>(self, other: I) -> bool
fn le<I>(self, other: I) -> bool
Iterator
are lexicographically
less or equal to those of another. Read more1.5.0 · Source§fn gt<I>(self, other: I) -> bool
fn gt<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than those of another. Read more1.5.0 · Source§fn ge<I>(self, other: I) -> bool
fn ge<I>(self, other: I) -> bool
Iterator
are lexicographically
greater than or equal to those of another. Read more