rama::crypto::dep::x509_parser::prelude::asn1_rs::nom::lib::std::iter

Trait IntoIterator

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

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

Available on crate features crypto and std only.

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§

1.0.0 (const: unstable) · Source

type Item

The type of the elements being iterated over.

1.0.0 (const: unstable) · Source

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

Which kind of iterator are we turning this into?

Required Methods§

1.0.0 (const: unstable) · Source

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

See the module-level documentation for more.

§Examples

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());

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§

§

impl IntoIterator for DupFlags

IntoIterator

Trait IntoIterator Copy item path

§Examples

Required Associated Types§

type Item

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

Required Methods§

fn into_iter(self) -> Self::IntoIter

§Examples

Dyn Compatibility§

Implementors§

impl IntoIterator for &FieldSet

type IntoIter = Iter

type Item = Field

impl IntoIterator for Access

type Item = Access

type IntoIter = Iter<Access>

impl IntoIterator for Array

type Item = Value

type IntoIter = Box<dyn Iterator<Item = Value>>

impl IntoIterator for ArrayOfTables

type Item = Table

type IntoIter = Box<dyn Iterator<Item = Table>>

impl IntoIterator for AtFlags

type Item = AtFlags

type IntoIter = Iter<AtFlags>

impl IntoIterator for Bytes

type Item = u8

type IntoIter = IntoIter<Bytes>

impl IntoIterator for BytesMut

type Item = u8

type IntoIter = IntoIter<BytesMut>

impl IntoIterator for CFConnectingIp

type Item = ForwardedElement

type IntoIter = CFConnectingIpIterator

impl IntoIterator for ClientIp

type Item = ForwardedElement

type IntoIter = ClientIpIterator

impl IntoIterator for CreateFlags

type Item = CreateFlags

type IntoIter = Iter<CreateFlags>

impl IntoIterator for DupFlags

type Item = DupFlags

type IntoIter = Iter<DupFlags>

impl IntoIterator for syn::error::Error

type Item = Error

type IntoIter = IntoIter

impl IntoIterator for syn::error::Error

type Item = Error

type IntoIter = IntoIter

impl IntoIterator for FallocateFlags

type Item = FallocateFlags

type IntoIter = Iter<FallocateFlags>

impl IntoIterator for FdFlags

type Item = FdFlags

type IntoIter = Iter<FdFlags>

impl IntoIterator for syn::data::Fields

type Item = Field

type IntoIter = IntoIter<Field>

impl IntoIterator for syn::data::Fields

type Item = Field

type IntoIter = IntoIter<Field>

impl IntoIterator for rama::net::forwarded::Forwarded

type Item = ForwardedElement

type IntoIter = Chain<Once<ForwardedElement>, IntoIter<ForwardedElement>>

impl IntoIterator for rama::http::headers::forwarded::Forwarded

type Item = <Forwarded as IntoIterator>::Item

type IntoIter = <Forwarded as IntoIterator>::IntoIter

impl IntoIterator for IFlags

type Item = IFlags

type IntoIter = Iter<IFlags>

impl IntoIterator for rand::seq::index_::IndexVec

type IntoIter = IndexVecIntoIter

type Item = usize

impl IntoIterator for IndexVec

type IntoIter = IndexVecIntoIter

type Item = usize

impl IntoIterator for InlineTable

type Item = (String, Value)

type IntoIter = Box<dyn Iterator<Item = (String, Value)>>

Trait IntoIterator