Struct openstack::common::ResourceIterator

pub struct ResourceIterator<Q: ResourceQuery> { /* fields omitted */ }

Generic implementation of a FallibleIterator over resources.

Implementations

impl<Q> ResourceIterator<Q> where
    Q: ResourceQuery, 

pub fn one(self) -> Result<Q::Item>

Assert that only one item is left and fetch it.

Fails with ResourceNotFound if no items are left and with TooManyItems if there is more than one item left.

Trait Implementations

impl<Q: Clone + ResourceQuery> Clone for ResourceIterator<Q> where
    Q::Item: Clone, 

fn clone(&self) -> ResourceIterator<Q>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Q: Debug + ResourceQuery> Debug for ResourceIterator<Q> where
    Q::Item: Debug, 

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Q> FallibleIterator for ResourceIterator<Q> where
    Q: ResourceQuery, 

type Item = Q::Item

The type being iterated over.

type Error = Error

The error type.

fn next(&mut self) -> Result<Option<Self::Item>>

Advances the iterator and returns the next value.

fn size_hint(&self) -> (usize, Option<usize>)

Returns bounds on the remaining length of the iterator.

fn count(self) -> Result<usize, Self::Error>

Consumes the iterator, returning the number of remaining items.

fn last(self) -> Result<Option<Self::Item>, Self::Error>

Returns the last element of the iterator.

fn nth(&mut self, n: usize) -> Result<Option<Self::Item>, Self::Error>

Returns the nth element of the iterator.

fn step_by(self, step: usize) -> StepBy<Self>

Returns an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<I>(self, it: I) -> Chain<Self, I> where
    I: IntoFallibleIterator<Item = Self::Item, Error = Self::Error>, 

Returns an iterator which yields the elements of this iterator followed by another.

fn zip<I>(
    self,
    o: I
) -> Zip<Self, <I as IntoFallibleIterator>::IntoFallibleIter> where
    I: IntoFallibleIterator<Error = Self::Error>, 

Returns an iterator that yields pairs of this iterator's and another iterator's values.

fn map<F, B>(self, f: F) -> Map<Self, F> where
    F: FnMut(Self::Item) -> Result<B, Self::Error>, 

Returns an iterator which applies a fallible transform to the elements of the underlying iterator.

fn for_each<F>(self, f: F) -> Result<(), Self::Error> where
    F: FnMut(Self::Item) -> Result<(), Self::Error>, 

Calls a fallible closure on each element of an iterator.

fn filter<F>(self, f: F) -> Filter<Self, F> where
    F: FnMut(&Self::Item) -> Result<bool, Self::Error>, 

Returns an iterator which uses a predicate to determine which values should be yielded. The predicate may fail; such failures are passed to the caller.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F> where
    F: FnMut(Self::Item) -> Result<Option<B>, Self::Error>, 

Returns an iterator which both filters and maps. The closure may fail; such failures are passed along to the consumer.

fn enumerate(self) -> Enumerate<Self>

Returns an iterator which yields the current iteration count as well as the value.

fn peekable(self) -> Peekable<Self>

Returns an iterator that can peek at the next element without consuming it.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P> where
    P: FnMut(&Self::Item) -> Result<bool, Self::Error>, 

Returns an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P> where
    P: FnMut(&Self::Item) -> Result<bool, Self::Error>, 

Returns an iterator that yields elements based on a predicate.

fn skip(self, n: usize) -> Skip<Self>

Returns an iterator which skips the first n values of this iterator.

fn take(self, n: usize) -> Take<Self>

Returns an iterator that yields only the first n values of this iterator.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F> where
    F: FnMut(&mut St, Self::Item) -> Result<Option<B>, Self::Error>, 

Returns an iterator which applies a stateful map to values of this iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F> where
    F: FnMut(Self::Item) -> Result<U, Self::Error>,
    U: IntoFallibleIterator<Error = Self::Error>, 

Returns an iterator which maps this iterator's elements to iterators, yielding those iterators' values.

fn flatten(self) -> Flatten<Self> where
    Self::Item: IntoFallibleIterator,
    <Self::Item as IntoFallibleIterator>::Error == Self::Error, 

Returns an iterator which flattens an iterator of iterators, yielding those iterators' values.

fn fuse(self) -> Fuse<Self>

Returns an iterator which yields this iterator's elements and ends after the first Ok(None).

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnMut(&Self::Item) -> Result<(), Self::Error>, 

Returns an iterator which passes each element to a closure before returning it.

fn by_ref(&mut self) -> &mut Self

Borrow an iterator rather than consuming it.

fn collect<T>(self) -> Result<T, Self::Error> where
    T: FromFallibleIterator<Self::Item>, 

Transforms the iterator into a collection.

fn partition<B, F>(self, f: F) -> Result<(B, B), Self::Error> where
    B: Default + Extend<Self::Item>,
    F: FnMut(&Self::Item) -> Result<bool, Self::Error>, 

Transforms the iterator into two collections, partitioning elements by a closure.

fn fold<B, F>(self, init: B, f: F) -> Result<B, Self::Error> where
    F: FnMut(B, Self::Item) -> Result<B, Self::Error>, 

Applies a function over the elements of the iterator, producing a single final value.

fn try_fold<B, E, F>(&mut self, init: B, f: F) -> Result<B, E> where
    E: From<Self::Error>,
    F: FnMut(B, Self::Item) -> Result<B, E>, 

Applies a function over the elements of the iterator, producing a single final value.

fn all<F>(&mut self, f: F) -> Result<bool, Self::Error> where
    F: FnMut(Self::Item) -> Result<bool, Self::Error>, 

Determines if all elements of this iterator match a predicate.

fn any<F>(&mut self, f: F) -> Result<bool, Self::Error> where
    F: FnMut(Self::Item) -> Result<bool, Self::Error>, 

Determines if any element of this iterator matches a predicate.

fn find<F>(&mut self, f: F) -> Result<Option<Self::Item>, Self::Error> where
    F: FnMut(&Self::Item) -> Result<bool, Self::Error>, 

Returns the first element of the iterator that matches a predicate.

fn find_map<B, F>(&mut self, f: F) -> Result<Option<B>, Self::Error> where
    F: FnMut(Self::Item) -> Result<Option<B>, Self::Error>, 

Applies a function to the elements of the iterator, returning the first non-None result.

fn position<F>(&mut self, f: F) -> Result<Option<usize>, Self::Error> where
    F: FnMut(Self::Item) -> Result<bool, Self::Error>, 

Returns the position of the first element of this iterator that matches a predicate. The predicate may fail; such failures are returned to the caller.

fn max(self) -> Result<Option<Self::Item>, Self::Error> where
    Self::Item: Ord, 

Returns the maximal element of the iterator.

fn max_by_key<B, F>(self, f: F) -> Result<Option<Self::Item>, Self::Error> where
    B: Ord,
    F: FnMut(&Self::Item) -> Result<B, Self::Error>, 

Returns the element of the iterator which gives the maximum value from the function.

fn max_by<F>(self, f: F) -> Result<Option<Self::Item>, Self::Error> where
    F: FnMut(&Self::Item, &Self::Item) -> Result<Ordering, Self::Error>, 

Returns the element that gives the maximum value with respect to the function.

fn min(self) -> Result<Option<Self::Item>, Self::Error> where
    Self::Item: Ord, 

Returns the minimal element of the iterator.

fn min_by_key<B, F>(self, f: F) -> Result<Option<Self::Item>, Self::Error> where
    B: Ord,
    F: FnMut(&Self::Item) -> Result<B, Self::Error>, 

Returns the element of the iterator which gives the minimum value from the function.

fn min_by<F>(self, f: F) -> Result<Option<Self::Item>, Self::Error> where
    F: FnMut(&Self::Item, &Self::Item) -> Result<Ordering, Self::Error>, 

Returns the element that gives the minimum value with respect to the function.

fn rev(self) -> Rev<Self> where
    Self: DoubleEndedFallibleIterator, 

Returns an iterator that yields this iterator's items in the opposite order.

fn unzip<A, B, FromA, FromB>(self) -> Result<(FromA, FromB), Self::Error> where
    FromA: Default + Extend<A>,
    FromB: Default + Extend<B>,
    Self: FallibleIterator<Item = (A, B)>, 

Converts an iterator of pairs into a pair of containers.

fn cloned<'a, T>(self) -> Cloned<Self> where
    Self: FallibleIterator<Item = &'a T>,
    T: 'a + Clone, 

Returns an iterator which clones all of its elements.

fn cycle(self) -> Cycle<Self> where
    Self: Clone, 

Returns an iterator which repeas this iterator endlessly.

fn cmp<I>(self, other: I) -> Result<Ordering, Self::Error> where
    I: IntoFallibleIterator<Item = Self::Item, Error = Self::Error>,
    Self::Item: Ord, 

Lexicographically compares the elements of this iterator to that of another.

fn partial_cmp<I>(self, other: I) -> Result<Option<Ordering>, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialOrd<<I as IntoFallibleIterator>::Item>, 

Lexicographically compares the elements of this iterator to that of another.

fn eq<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialEq<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are equal to those of another.

fn ne<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialEq<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are not equal to those of another.

fn lt<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialOrd<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialOrd<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are lexicographically less than or equal to those of another.

fn gt<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialOrd<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> Result<bool, Self::Error> where
    I: IntoFallibleIterator<Error = Self::Error>,
    Self::Item: PartialOrd<<I as IntoFallibleIterator>::Item>, 

Determines if the elements of this iterator are lexicographically greater than or equal to those of another.

fn iterator(self) -> Iterator<Self>

Returns a normal (non-fallible) iterator over Result<Item, Error>.

fn map_err<B, F>(self, f: F) -> MapErr<Self, F> where
    F: FnMut(Self::Error) -> B, 

Returns an iterator which applies a transform to the errors of the underlying iterator.