Trait gclient::ext::sp_core::sp_std::iter::Extend

pub trait Extend<A> {
    // Required method
    fn extend<T>(&mut self, iter: T)
       where T: IntoIterator<Item = A>;

    // Provided methods
    fn extend_one(&mut self, item: A) { ... }
    fn extend_reserve(&mut self, additional: usize) { ... }
}

Extend a collection with the contents of an iterator.

Iterators produce a series of values, and collections can also be thought of as a series of values. The Extend trait bridges this gap, allowing you to extend a collection by including the contents of that iterator. When extending a collection with an already existing key, that entry is updated or, in the case of collections that permit multiple entries with equal keys, that entry is inserted.

Examples

Basic usage:

// You can extend a String with some chars:
let mut message = String::from("The first three letters are: ");

message.extend(&['a', 'b', 'c']);

assert_eq!("abc", &message[29..32]);

Implementing Extend:

// 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);
    }
}

// since MyCollection has a list of i32s, we implement Extend for i32
impl Extend<i32> for MyCollection {

    // This is a bit simpler with the concrete type signature: we can call
    // extend on anything which can be turned into an Iterator which gives
    // us i32s. Because we need i32s to put into MyCollection.
    fn extend<T: IntoIterator<Item=i32>>(&mut self, iter: T) {

        // The implementation is very straightforward: loop through the
        // iterator, and add() each element to ourselves.
        for elem in iter {
            self.add(elem);
        }
    }
}

let mut c = MyCollection::new();

c.add(5);
c.add(6);
c.add(7);

// let's extend our collection with three more numbers
c.extend(vec![1, 2, 3]);

// we've added these elements onto the end
assert_eq!("MyCollection([5, 6, 7, 1, 2, 3])", format!("{c:?}"));

Required Methods

fn extend<T>(&mut self, iter: T)

where T: IntoIterator<Item = A>,

Extends a collection with the contents of an iterator.

As this is the only required method for this trait, the trait-level docs contain more details.

Examples

// You can extend a String with some chars:
let mut message = String::from("abc");

message.extend(['d', 'e', 'f'].iter());

assert_eq!("abcdef", &message);

Provided Methods

fn extend_one(&mut self, item: A)

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

Extends a collection with exactly one element.

fn extend_reserve(&mut self, additional: usize)

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

Reserves capacity in a collection for the given number of additional elements.

The default implementation does nothing.

Object Safety

This trait is not object safe.

Implementors

impl Extend<(String, Value)> for Map<String, Value>

impl Extend<char> for String

impl Extend<u8> for BytesMut

impl Extend<()> for ()

impl Extend<Capabilities> for Capabilities

impl Extend<String> for String

impl Extend<Box<str>> for String

impl Extend<OsString> for OsString

impl Extend<Access> for Access

impl Extend<Access> for Access

impl Extend<AtFlags> for AtFlags

impl Extend<AtFlags> for AtFlags

impl Extend<Bytes> for BytesMut

impl Extend<ControlModes> for ControlModes

impl Extend<CreateFlags> for CreateFlags

impl Extend<CreateFlags> for CreateFlags

impl Extend<CreateFlags> for CreateFlags

impl Extend<CreateFlags> for CreateFlags

impl Extend<DupFlags> for DupFlags

impl Extend<DupFlags> for DupFlags

impl Extend<DupFlags> for DupFlags

impl Extend<EventFlags> for EventFlags

impl Extend<EventFlags> for EventFlags

impl Extend<EventfdFlags> for EventfdFlags

impl Extend<EventfdFlags> for EventfdFlags

impl Extend<Extensions> for Extensions

impl Extend<FallocateFlags> for FallocateFlags

impl Extend<FallocateFlags> for FallocateFlags

impl Extend<FdFlags> for FdFlags

impl Extend<FdFlags> for FdFlags

impl Extend<FdFlags> for FdFlags

impl Extend<IFlags> for IFlags

impl Extend<InputModes> for InputModes

impl Extend<LocalModes> for LocalModes

impl Extend<MapFlags> for MapFlags

impl Extend<MemfdFlags> for MemfdFlags

impl Extend<MemfdFlags> for MemfdFlags

impl Extend<MlockFlags> for MlockFlags

impl Extend<Mode> for Mode

impl Extend<Mode> for Mode

impl Extend<MountFlags> for MountFlags

impl Extend<MountFlags> for MountFlags

impl Extend<MountPropagationFlags> for MountPropagationFlags

impl Extend<MountPropagationFlags> for MountPropagationFlags

impl Extend<MprotectFlags> for MprotectFlags

impl Extend<MremapFlags> for MremapFlags

impl Extend<MsyncFlags> for MsyncFlags

impl Extend<OFlags> for OFlags

impl Extend<OFlags> for OFlags

impl Extend<OutputModes> for OutputModes

impl Extend<PipeFlags> for PipeFlags

impl Extend<PipeFlags> for PipeFlags

impl Extend<PollFlags> for PollFlags

impl Extend<PollFlags> for PollFlags

impl Extend<ProtFlags> for ProtFlags

impl Extend<Protection> for Protection

impl Extend<ReadWriteFlags> for ReadWriteFlags

impl Extend<ReadWriteFlags> for ReadWriteFlags

impl Extend<ReadWriteFlags> for ReadWriteFlags

impl Extend<RenameFlags> for RenameFlags

impl Extend<RenameFlags> for RenameFlags

impl Extend<ResolveFlags> for ResolveFlags

impl Extend<ResolveFlags> for ResolveFlags

impl Extend<SealFlags> for SealFlags

impl Extend<SealFlags> for SealFlags

impl Extend<SpliceFlags> for SpliceFlags

impl Extend<SpliceFlags> for SpliceFlags

impl Extend<StatVfsMountFlags> for StatVfsMountFlags

impl Extend<StatVfsMountFlags> for StatVfsMountFlags

impl Extend<StatxFlags> for StatxFlags

impl Extend<StatxFlags> for StatxFlags

impl Extend<UnmountFlags> for UnmountFlags

impl Extend<UnmountFlags> for UnmountFlags

impl Extend<UserfaultfdFlags> for UserfaultfdFlags

impl Extend<WatchFlags> for WatchFlags

impl Extend<WatchFlags> for WatchFlags

impl Extend<XattrFlags> for XattrFlags

impl Extend<XattrFlags> for XattrFlags

impl<'a> Extend<&'a char> for String

impl<'a> Extend<&'a str> for String

impl<'a> Extend<&'a u8> for BytesMut

impl<'a> Extend<&'a OsStr> for OsString

impl<'a> Extend<Cow<'a, str>> for String

impl<'a> Extend<Cow<'a, OsStr>> for OsString

impl<'a, K, V> Extend<(&'a K, &'a V)> for IndexMap<K, V>

where K: Ord + Copy, V: Copy,

impl<'a, K, V, A> Extend<(&'a K, &'a V)> for BTreeMap<K, V, A>

where K: Ord + Copy, V: Copy, A: Allocator + Clone,

impl<'a, K, V, S> Extend<(&'a K, &'a V)> for std::collections::hash::map::HashMap<K, V, S>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher,

impl<'a, K, V, S> Extend<(&'a K, &'a V)> for indexmap::map::IndexMap<K, V, S>

where K: Hash + Eq + Copy, V: Copy, S: BuildHasher,

impl<'a, K, V, S> Extend<(&'a K, &'a V)> for AHashMap<K, V, S>

where K: Eq + Hash + Copy + 'a, V: Copy + 'a, S: BuildHasher,

impl<'a, K, V, S> Extend<(&'a K, &'a V)> for IndexMap<K, V, S>

where K: Hash + Eq + Copy, V: Copy, S: BuildHasher,

impl<'a, K, V, S, A> Extend<&'a (K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, K, V, S, A> Extend<&'a (K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, K, V, S, A> Extend<&'a (K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, K, V, S, A> Extend<(&'a K, &'a V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, K, V, S, A> Extend<(&'a K, &'a V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, K, V, S, A> Extend<(&'a K, &'a V)> for HashMap<K, V, S, A>

where K: Eq + Hash + Copy, V: Copy, S: BuildHasher, A: Allocator,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<'a, M, T1, T2, O1, O2> Extend<BitRef<'a, M, T2, O2>> for BitVec<T1, O1>

where M: Mutability, T1: BitStore, T2: BitStore, O1: BitOrder, O2: BitOrder,

Bit-Vector Extension by Proxy References

DO NOT use this. You clearly have a bit-slice. Use .extend_from_bitslice() instead!

Iterating over a bit-slice requires loading from memory and constructing a proxy reference for each bit. This is needlessly slow; the specialized method is able to avoid this per-bit cost and possibly even use batched operations.

impl<'a, T> Extend<&'a T> for IndexSet<T>

where T: Ord + Copy,

impl<'a, T, A> Extend<&'a T> for gclient::ext::sp_runtime::app_crypto::Vec<T, A>

where T: Copy + 'a, A: Allocator,

Extend implementation that copies elements out of references before pushing them onto the Vec.

This implementation is specialized for slice iterators, where it uses copy_from_slice to append the entire slice at once.

impl<'a, T, A> Extend<&'a T> for BTreeSet<T, A>

where T: 'a + Ord + Copy, A: Allocator + Clone,

impl<'a, T, A> Extend<&'a T> for BinaryHeap<T, A>

where T: 'a + Ord + Copy, A: Allocator,

impl<'a, T, A> Extend<&'a T> for LinkedList<T, A>

where T: 'a + Copy, A: Allocator,

impl<'a, T, A> Extend<&'a T> for VecDeque<T, A>

where T: 'a + Copy, A: Allocator,

impl<'a, T, A> Extend<&'a T> for Vec<T, A>

where T: Copy + 'a, A: Allocator + 'a,

Extend implementation that copies elements out of references before pushing them onto the Vec.

This implementation is specialized for slice iterators, where it uses copy_from_slice to append the entire slice at once.

impl<'a, T, O> Extend<&'a bool> for BitVec<T, O>

where T: BitStore, O: BitOrder,

impl<'a, T, O> Extend<&'a T> for BitVec<T, O>

where T: BitStore, O: BitOrder,

impl<'a, T, S> Extend<&'a T> for std::collections::hash::set::HashSet<T, S>

where T: 'a + Eq + Hash + Copy, S: BuildHasher,

impl<'a, T, S> Extend<&'a T> for indexmap::set::IndexSet<T, S>

where T: Hash + Eq + Copy + 'a, S: BuildHasher,

impl<'a, T, S> Extend<&'a T> for AHashSet<T, S>

where T: 'a + Eq + Hash + Copy, S: BuildHasher,

impl<'a, T, S> Extend<&'a T> for IndexSet<T, S>

where T: Hash + Eq + Copy + 'a, S: BuildHasher,

impl<'a, T, S, A> Extend<&'a T> for HashSet<T, S, A>

where T: 'a + Eq + Hash + Copy, S: BuildHasher, A: Allocator + Clone,

impl<'a, T, S, A> Extend<&'a T> for HashSet<T, S, A>

where T: 'a + Eq + Hash + Copy, S: BuildHasher, A: Allocator + Clone,

impl<'a, T, S, A> Extend<&'a T> for HashSet<T, S, A>

where T: 'a + Eq + Hash + Copy, S: BuildHasher, A: Allocator,

impl<'s, T> Extend<T> for SliceVec<'s, T>

impl<A> Extend<<A as Array>::Item> for arrayvec::ArrayVec<A>

where A: Array,

Extend the ArrayVec with an iterator.

Does not extract more items than there is space for. No error occurs if there are more iterator elements.

impl<A> Extend<<A as Array>::Item> for arrayvec::ArrayVec<A>

where A: Array,

Extend the ArrayVec with an iterator.

Does not extract more items than there is space for. No error occurs if there are more iterator elements.

impl<A> Extend<<A as Array>::Item> for ArrayVec<A>

where A: Array,

impl<A> Extend<<A as Array>::Item> for SmallVec<A>

where A: Array,

impl<A> Extend<<A as Array>::Item> for TinyVec<A>

where A: Array,

impl<A> Extend<A> for NonEmpty<A>

impl<A> Extend<Box<str, A>> for String

where A: Allocator,

impl<A, B, ExtendA, ExtendB> Extend<(A, B)> for (ExtendA, ExtendB)

where ExtendA: Extend<A>, ExtendB: Extend<B>,

impl<Fut> Extend<Fut> for FuturesOrdered<Fut>

where Fut: Future,

impl<Fut> Extend<Fut> for FuturesUnordered<Fut>

impl<K, V> Extend<(K, V)> for IndexMap<K, V>

where K: Ord + Clone,

impl<K, V> Extend<(K, V)> for StreamMap<K, V>

impl<K, V, A> Extend<(K, V)> for BTreeMap<K, V, A>

where K: Ord, A: Allocator + Clone,

impl<K, V, S> Extend<(K, V)> for std::collections::hash::map::HashMap<K, V, S>

where K: Eq + Hash, S: BuildHasher,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<K, V, S> Extend<(K, V)> for indexmap::map::IndexMap<K, V, S>

where K: Hash + Eq, S: BuildHasher,

impl<K, V, S> Extend<(K, V)> for AHashMap<K, V, S>

where K: Eq + Hash, S: BuildHasher,

impl<K, V, S> Extend<(K, V)> for IndexMap<K, V, S>

where K: Hash + Eq, S: BuildHasher,

impl<K, V, S, A> Extend<(K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<K, V, S, A> Extend<(K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash, S: BuildHasher, A: Allocator + Clone,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<K, V, S, A> Extend<(K, V)> for HashMap<K, V, S, A>

where K: Eq + Hash, S: BuildHasher, A: Allocator,

Inserts all new key-values from the iterator and replaces values with existing keys with new values returned from the iterator.

impl<L, R, A> Extend<A> for Either<L, R>

where L: Extend<A>, R: Extend<A>,

impl<P> Extend<P> for PathBuf

where P: AsRef<Path>,

impl<St> Extend<St> for SelectAll<St>

where St: Stream + Unpin,

impl<T> Extend<(Option<HeaderName>, T)> for HeaderMap<T>

impl<T> Extend<(HeaderName, T)> for HeaderMap<T>

impl<T> Extend<T> for IndexSet<T>

where T: Ord + Clone,

impl<T, A> Extend<T> for gclient::ext::sp_runtime::app_crypto::Vec<T, A>

where A: Allocator,

impl<T, A> Extend<T> for BTreeSet<T, A>

where T: Ord, A: Allocator + Clone,

impl<T, A> Extend<T> for BinaryHeap<T, A>

where T: Ord, A: Allocator,

impl<T, A> Extend<T> for LinkedList<T, A>

where A: Allocator,

impl<T, A> Extend<T> for VecDeque<T, A>

where A: Allocator,

impl<T, A> Extend<T> for Vec<T, A>

where A: Allocator,

impl<T, L> Extend<(T, L)> for Targets

where T: Into<String>, L: Into<LevelFilter>,

impl<T, O> Extend<bool> for BitVec<T, O>

where T: BitStore, O: BitOrder,

Bit-Vector Extension

This extends a bit-vector from anything that produces individual bits.

Original

impl<T> Extend<T> for Vec<T>

Notes

This .extend() call is the second-slowest possible way to append bits into a bit-vector, faster only than calling iter.for_each(|bit| bv.push(bit)). DO NOT use this if you have any other choice.

If you are extending a bit-vector from the contents of a bit-slice, then you should use .extend_from_bitslice() instead. That method is specialized to perform upfront allocation and, where possible, use a batch copy rather than copying each bit individually from the source into the bit-vector.

impl<T, O> Extend<T> for BitVec<T, O>

where T: BitStore, O: BitOrder,

impl<T, S> Extend<T> for std::collections::hash::set::HashSet<T, S>

where T: Eq + Hash, S: BuildHasher,

impl<T, S> Extend<T> for indexmap::set::IndexSet<T, S>

where T: Hash + Eq, S: BuildHasher,

impl<T, S> Extend<T> for AHashSet<T, S>

where T: Eq + Hash, S: BuildHasher,

impl<T, S> Extend<T> for IndexSet<T, S>

where T: Hash + Eq, S: BuildHasher,

impl<T, S, A> Extend<T> for HashSet<T, S, A>

where T: Eq + Hash, S: BuildHasher, A: Allocator + Clone,

impl<T, S, A> Extend<T> for HashSet<T, S, A>

where T: Eq + Hash, S: BuildHasher, A: Allocator + Clone,

impl<T, S, A> Extend<T> for HashSet<T, S, A>

where T: Eq + Hash, S: BuildHasher, A: Allocator,

impl<T, const CAP: usize> Extend<T> for arrayvec::arrayvec::ArrayVec<T, CAP>

Extend the ArrayVec with an iterator.

Panics if extending the vector exceeds its capacity.