Struct dbus::arg::Iter

pub struct Iter<'a>(_, _, _);

Helper struct for retrieve one or more arguments from a Message.

Implementations

impl<'a> Iter<'a>

pub fn new(m: &'a Message) -> Iter<'a>

Creates a new struct for iterating over the arguments of a message, starting with the first argument.

pub fn get<T: Get<'a>>(&mut self) -> Option<T>

Returns the current argument, if T is the argument type. Otherwise returns None.

pub fn get_refarg(&mut self) -> Option<Box<dyn RefArg + 'static>>

Returns the current argument as a trait object.

See the argument guide’s reference part for information on what types hide inside the RefArg.

pub fn signature(&mut self) -> Signature<'static>

Returns the type signature for the current argument.

pub fn arg_type(&mut self) -> ArgType

The raw arg_type for the current item.

Unlike Arg::arg_type, this requires access to self and is not a static method. You can match this against Arg::arg_type for different types to understand what type the current item is. In case you’re past the last argument, this function will return 0.

pub fn next(&mut self) -> bool

Returns false if there are no more items.

pub fn read<T: Arg + Get<'a>>(&mut self) -> Result<T, TypeMismatchError>

Wrapper around get and next. Calls get, and then next if get succeeded.

Also returns a Result rather than an Option to give an error if successful.

Example

struct ServiceBrowserItemNew {
    interface: i32,
    protocol: i32,
    name: String,
    item_type: String,
    domain: String,
    flags: u32,
}

fn service_browser_item_new_msg(m: &Message) -> Result<ServiceBrowserItemNew, TypeMismatchError> {
    let mut iter = m.iter_init();
    Ok(ServiceBrowserItemNew {
        interface: iter.read()?,
        protocol: iter.read()?,
        name: iter.read()?,
        item_type: iter.read()?,
        domain: iter.read()?,
        flags: iter.read()?,
    })
}

pub fn recurse(&mut self, arg_type: ArgType) -> Option<Iter<'a>>

If the current argument is a container of the specified arg_type, then a new Iter is returned which is for iterating over the contents inside the container.

Primarily for internal use (the “get” function is more ergonomic), but could be useful for recursing into containers with unknown types.

Trait Implementations

impl<'a> Clone for Iter<'a>

fn clone(&self) -> Iter<'a>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for Iter<'a>

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

Formats the value using the given formatter.

impl<'a> Iterator for Iter<'a>

type Item = Box<dyn RefArg + 'static, Global>

The type of the elements being iterated over.

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

Advances the iterator and returns the next value.

fn next_chunk<const N: usize>(
    &mut self
) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>where
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_next_chunk)

Advances the iterator and returns an array containing the next N values.

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

Returns the bounds on the remaining length of the iterator.

fn count(self) -> usizewhere
    Self: Sized,

Consumes the iterator, counting the number of iterations and returning it.

fn last(self) -> Option<Self::Item>where
    Self: Sized,

Consumes the iterator, returning the last element.

fn advance_by(&mut self, n: usize) -> Result<(), usize>

🔬This is a nightly-only experimental API. (iter_advance_by)

Advances the iterator by n elements.

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

Returns the nth element of the iterator.

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

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

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>where
    Self: Sized,
    U: IntoIterator<Item = Self::Item>,

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>where
    Self: Sized,
    U: IntoIterator,

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>where
    Self: Sized,
    G: FnMut() -> Self::Item,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

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

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F)where
    Self: Sized,
    F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Creates an iterator which uses a closure to determine if an element should be yielded.

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

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>where
    Self: Sized,

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>where
    Self: Sized,

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

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

Creates an iterator that skips elements based on a predicate.

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

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>where
    Self: Sized,
    P: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both yields elements based on a predicate and maps.

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

Creates an iterator that skips the first n elements.

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

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

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

An iterator adapter which, like fold, holds internal state, but unlike fold, produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>where
    Self: Sized,
    U: IntoIterator,
    F: FnMut(Self::Item) -> U,

Creates an iterator that works like map, but flattens nested structure.

fn fuse(self) -> Fuse<Self>where
    Self: Sized,

Creates an iterator which ends after the first None.

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

Does something with each element of an iterator, passing the value on.

fn by_ref(&mut self) -> &mut Selfwhere
    Self: Sized,

Borrows an iterator, rather than consuming it.

fn collect<B>(self) -> Bwhere
    B: FromIterator<Self::Item>,
    Self: Sized,

Transforms an iterator into a collection.

fn collect_into<E>(self, collection: &mut E) -> &mut Ewhere
    E: Extend<Self::Item>,
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_collect_into)

Collects all the items from an iterator into a collection.

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

Consumes an iterator, creating two collections from it.

fn is_partitioned<P>(self, predicate: P) -> boolwhere
    Self: Sized,
    P: FnMut(Self::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_is_partitioned)

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> Rwhere
    Self: Sized,
    F: FnMut(B, Self::Item) -> R,
    R: Try<Output = B>,

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> Rwhere
    Self: Sized,
    F: FnMut(Self::Item) -> R,
    R: Try<Output = ()>,

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> Bwhere
    Self: Sized,
    F: FnMut(B, Self::Item) -> B,

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(Self::Item, Self::Item) -> Self::Item,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn try_reduce<F, R>(
    &mut self,
    f: F
) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryTypewhere
    Self: Sized,
    F: FnMut(Self::Item, Self::Item) -> R,
    R: Try<Output = Self::Item>,
    <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (iterator_try_reduce)

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately.

fn all<F>(&mut self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item>where
    Self: Sized,
    P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator that satisfies a predicate.

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

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<F, R>(
    &mut self,
    f: F
) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryTypewhere
    Self: Sized,
    F: FnMut(&Self::Item) -> R,
    R: Try<Output = bool>,
    <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (try_find)

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize>where
    Self: Sized,
    P: FnMut(Self::Item) -> bool,

Searches for an element in an iterator, returning its index.

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

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Ordering,

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

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

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item>where
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Ordering,

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

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

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self>where
    T: 'a + Copy,
    Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which copies all of its elements.

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

Creates an iterator which clones all of its elements.

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

Repeats an iterator endlessly.

fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>where
    Self: Sized,

🔬This is a nightly-only experimental API. (iter_array_chunks)

Returns an iterator over N elements of the iterator at a time.

fn sum<S>(self) -> Swhere
    Self: Sized,
    S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> Pwhere
    Self: Sized,
    P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp_by<I, F>(self, other: I, cmp: F) -> Orderingwhere
    Self: Sized,
    I: IntoIterator,
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn partial_cmp<I>(self, other: I) -> Option<Ordering>where
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

Lexicographically compares the elements of this Iterator with those of another.

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>,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>,
    Self: Sized,

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

fn eq_by<I, F>(self, other: I, eq: F) -> boolwhere
    Self: Sized,
    I: IntoIterator,
    F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialEq<<I as IntoIterator>::Item>,
    Self: Sized,

Determines if the elements of this Iterator are unequal to those of another.

fn lt<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

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

fn le<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

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

fn gt<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

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

fn ge<I>(self, other: I) -> boolwhere
    I: IntoIterator,
    Self::Item: PartialOrd<<I as IntoIterator>::Item>,
    Self: Sized,

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

fn is_sorted_by<F>(self, compare: F) -> boolwhere
    Self: Sized,
    F: FnMut(&Self::Item, &Self::Item) -> Option<Ordering>,

🔬This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> boolwhere
    Self: Sized,
    F: FnMut(Self::Item) -> K,
    K: PartialOrd<K>,

🔬This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this iterator are sorted using the given key extraction function.

impl<'a> Copy for Iter<'a>