Trait druid::piet::cairo::glib::bitflags::_core::iter::IntoIterator

1.0.0 · source ·

pub trait IntoIterator {
    type Item;
    type IntoIter: Iterator<Item = Self::Item>;

    // Required method
    fn into_iter(self) -> Self::IntoIter;
}

Expand description

Conversion into an Iterator.

By implementing IntoIterator for a type, you define how it will be converted to an iterator. This is common for types which describe a collection of some kind.

One benefit of implementing IntoIterator is that your type will work with Rust’s for loop syntax.

Examples

Basic usage:

let v = [1, 2, 3];
let mut iter = v.into_iter();

assert_eq!(Some(1), iter.next());
assert_eq!(Some(2), iter.next());
assert_eq!(Some(3), iter.next());
assert_eq!(None, iter.next());

Implementing IntoIterator for your type:

// A sample collection, that's just a wrapper over Vec<T>
#[derive(Debug)]
struct MyCollection(Vec<i32>);

// Let's give it some methods so we can create one and add things
// to it.
impl MyCollection {
    fn new() -> MyCollection {
        MyCollection(Vec::new())
    }

    fn add(&mut self, elem: i32) {
        self.0.push(elem);
    }
}

// and we'll implement IntoIterator
impl IntoIterator for MyCollection {
    type Item = i32;
    type IntoIter = std::vec::IntoIter<Self::Item>;

    fn into_iter(self) -> Self::IntoIter {
        self.0.into_iter()
    }
}

// Now we can make a new collection...
let mut c = MyCollection::new();

// ... add some stuff to it ...
c.add(0);
c.add(1);
c.add(2);

// ... and then turn it into an Iterator:
for (i, n) in c.into_iter().enumerate() {
    assert_eq!(i as i32, n);
}

It is common to use IntoIterator as a trait bound. This allows the input collection type to change, so long as it is still an iterator. Additional bounds can be specified by restricting on Item:

fn collect_as_strings<T>(collection: T) -> Vec<String>
where
    T: IntoIterator,
    T::Item: std::fmt::Debug,
{
    collection
        .into_iter()
        .map(|item| format!("{item:?}"))
        .collect()
}

Required Associated Types§

source

type Item

The type of the elements being iterated over.

source

type IntoIter: Iterator<Item = Self::Item>

Which kind of iterator are we turning this into?

Required Methods§

source

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

See the module-level documentation for more.

Examples

Basic usage:

let v = [1, 2, 3];
let mut iter = v.into_iter();

assert_eq!(Some(1), iter.next());
assert_eq!(Some(2), iter.next());
assert_eq!(Some(3), iter.next());
assert_eq!(None, iter.next());

Implementors§

§

impl IntoIterator for druid::piet::kurbo::BezPath

Trait druid::piet::cairo::glib::bitflags::_core::iter::IntoIterator

Examples

Required Associated Types§

type Item

type IntoIter: Iterator<Item = Self::Item>

Required Methods§

fn into_iter(self) -> Self::IntoIter

Examples

Implementors§

impl IntoIterator for druid::piet::kurbo::BezPath

type Item = PathEl

type IntoIter = IntoIter<PathEl, Global>

impl IntoIterator for Targets

type Item = (String, LevelFilter)

type IntoIter = IntoIter

impl IntoIterator for BezPath

type Item = PathEl

type IntoIter = IntoIter<PathEl, Global>

impl IntoIterator for CharRange

type IntoIter = CharIter

type Item = char

impl IntoIterator for FileAttributeMatcher

type Item = GString

type IntoIter = FileAttributematcherIter

impl IntoIterator for SetMatches

type IntoIter = SetMatchesIntoIter

type Item = usize

impl IntoIterator for SetMatches

type IntoIter = SetMatchesIntoIter

type Item = usize

impl<'a> IntoIterator for &'a druid::piet::kurbo::BezPath

type Item = PathEl

type IntoIter = Cloned<Iter<'a, PathEl>>

impl<'a> IntoIterator for &'a UnixListener

type Item = Result<UnixStream, Error>

type IntoIter = Incoming<'a>

impl<'a> IntoIterator for &'a Path

type Item = &'a OsStr

type IntoIter = Iter<'a>

impl<'a> IntoIterator for &'a PathBuf

type Item = &'a OsStr

type IntoIter = Iter<'a>

impl<'a> IntoIterator for &'a FieldSet

type IntoIter = Iter

type Item = Field

impl<'a> IntoIterator for &'a Targets

type Item = (&'a str, LevelFilter)

type IntoIter = Iter<'a>

impl<'a> IntoIterator for &'a BezPath

type Item = PathEl

type IntoIter = Cloned<Iter<'a, PathEl>>

impl<'a> IntoIterator for &'a ListModel

type Item = Result<Object, ListModelMutatedDuringIter>

type IntoIter = ListModelIter<'a, Object>

impl<'a> IntoIterator for &'a ListStore

type Item = <&'a ListModel as IntoIterator>::Item

type IntoIter = <&'a ListModel as IntoIterator>::IntoIter

impl<'a> IntoIterator for &'a SetMatches

type IntoIter = SetMatchesIter<'a>

type Item = usize

impl<'a> IntoIterator for &'a SetMatches

type IntoIter = SetMatchesIter<'a>

type Item = usize

impl<'a> IntoIterator for &'a Utf8Sequence

type IntoIter = Iter<'a, Utf8Range>

type Item = &'a Utf8Range

impl<'a> IntoIterator for Chains<'a>

type Item = Chain<'a>

type IntoIter = ChainsIter<'a>

impl<'a> IntoIterator for FeatureNames<'a>

type Item = FeatureName<'a>

type IntoIter = FeatureNamesIter<'a>

impl<'a> IntoIterator for Names<'a>

type Item = Name<'a>

type IntoIter = NamesIter<'a>

impl<'a> IntoIterator for SegmentMaps<'a>

type Item = LazyArray16<'a, AxisValueMap>

type IntoIter = SegmentMapsIter<'a>

impl<'a> IntoIterator for Strikes<'a>

type Item = Strike<'a>