Trait enso_prelude::iter::Extend 1.0.0[−][src]
pub trait Extend<A> { fn extend<T>(&mut self, iter: T)
where
T: IntoIterator<Item = A>; fn extend_one(&mut self, item: A) { ... } fn extend_reserve(&mut self, additional: usize) { ... } }
Expand description
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>,
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
Basic usage:
// 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)
fn extend_one(&mut self, item: A)
extend_one
)Extends a collection with exactly one element.
fn extend_reserve(&mut self, additional: usize)
fn extend_reserve(&mut self, additional: usize)
extend_one
)Reserves capacity in a collection for the given number of additional elements.
The default implementation does nothing.
Implementations on Foreign Types
extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)extend_one
)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.
extend_one
)extend_one
)impl<K, V, S> Extend<(<K as WeakElement>::Strong, <V as WeakElement>::Strong)> for PtrWeakWeakHashMap<K, V, S> where
S: BuildHasher,
K: WeakElement,
V: WeakElement,
<K as WeakElement>::Strong: Deref,
impl<K, V, S> Extend<(<K as WeakElement>::Strong, <V as WeakElement>::Strong)> for PtrWeakWeakHashMap<K, V, S> where
S: BuildHasher,
K: WeakElement,
V: WeakElement,
<K as WeakElement>::Strong: Deref,
pub fn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = (<K as WeakElement>::Strong, <V as WeakElement>::Strong)>,
impl<K, V, S> Extend<(<K as WeakElement>::Strong, V)> for PtrWeakKeyHashMap<K, V, S> where
S: BuildHasher,
K: WeakElement,
<K as WeakElement>::Strong: Deref,
impl<K, V, S> Extend<(<K as WeakElement>::Strong, V)> for PtrWeakKeyHashMap<K, V, S> where
S: BuildHasher,
K: WeakElement,
<K as WeakElement>::Strong: Deref,
pub fn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = (<K as WeakElement>::Strong, V)>,
impl<'a, K, V, S> Extend<(&'a <K as WeakElement>::Strong, &'a V)> for PtrWeakKeyHashMap<K, V, S> where
S: BuildHasher,
K: 'a + WeakElement,
V: 'a + Clone,
<K as WeakElement>::Strong: Clone,
<K as WeakElement>::Strong: Deref,
impl<'a, K, V, S> Extend<(&'a <K as WeakElement>::Strong, &'a V)> for PtrWeakKeyHashMap<K, V, S> where
S: BuildHasher,
K: 'a + WeakElement,
V: 'a + Clone,
<K as WeakElement>::Strong: Clone,
<K as WeakElement>::Strong: Deref,
pub fn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = (&'a <K as WeakElement>::Strong, &'a V)>,
impl<T, S> Extend<<T as WeakElement>::Strong> for PtrWeakHashSet<T, S> where
T: WeakElement,
S: BuildHasher,
<T as WeakElement>::Strong: Deref,
impl<T, S> Extend<<T as WeakElement>::Strong> for PtrWeakHashSet<T, S> where
T: WeakElement,
S: BuildHasher,
<T as WeakElement>::Strong: Deref,
impl<T, S> Extend<<T as WeakElement>::Strong> for WeakHashSet<T, S> where
T: WeakKey,
S: BuildHasher,
impl<T, S> Extend<<T as WeakElement>::Strong> for WeakHashSet<T, S> where
T: WeakKey,
S: BuildHasher,
impl<K, V, S> Extend<(<K as WeakElement>::Strong, <V as WeakElement>::Strong)> for WeakWeakHashMap<K, V, S> where
S: BuildHasher,
K: WeakKey,
V: WeakElement,
impl<K, V, S> Extend<(<K as WeakElement>::Strong, <V as WeakElement>::Strong)> for WeakWeakHashMap<K, V, S> where
S: BuildHasher,
K: WeakKey,
V: WeakElement,
pub fn extend<T>(&mut self, iter: T) where
T: IntoIterator<Item = (<K as WeakElement>::Strong, <V as WeakElement>::Strong)>,
Extend the number of columns of the Matrix
with elements from
a given iterator.
Extend the number of columns of the Matrix
with elements
from the given iterator.
Example
let data = vec![0, 1, 2, // column 1 3, 4, 5]; // column 2 let mut matrix = DMatrix::from_vec(3, 2, data); matrix.extend(vec![6, 7, 8]); // column 3 assert!(matrix.eq(&Matrix3::new(0, 3, 6, 1, 4, 7, 2, 5, 8)));
Panics
This function panics if the number of elements yielded by the
given iterator is not a multiple of the number of rows of the
Matrix
.
let data = vec![0, 1, 2, // column 1 3, 4, 5]; // column 2 let mut matrix = DMatrix::from_vec(3, 2, data); // The following panics because the vec length is not a multiple of 3. matrix.extend(vec![6, 7, 8, 9]);
Extend the number of rows of the Vector
with elements from
a given iterator.
Extend the number of rows of a Vector
with elements
from the given iterator.
Example
let mut vector = DVector::from_vec(vec![0, 1, 2]); vector.extend(vec![3, 4, 5]); assert!(vector.eq(&DVector::from_vec(vec![0, 1, 2, 3, 4, 5])));
Extends the number of columns of the VecStorage
with elements
from the given iterator.
Panics
This function panics if the number of elements yielded by the
given iterator is not a multiple of the number of rows of the
VecStorage
.
pub fn extend<I>(&mut self, iter: I) where
I: IntoIterator<Item = Matrix<T, RV, Const<1_usize>, SV>>,
pub fn extend<I>(&mut self, iter: I) where
I: IntoIterator<Item = Matrix<T, RV, Const<1_usize>, SV>>,
Extends the number of columns of a Matrix
with Vector
s
from a given iterator.
Example
let data = vec![0, 1, 2, // column 1 3, 4, 5]; // column 2 let mut matrix = DMatrix::from_vec(3, 2, data); matrix.extend( vec![Vector3::new(6, 7, 8), // column 3 Vector3::new(9, 10, 11)]); // column 4 assert!(matrix.eq(&Matrix3x4::new(0, 3, 6, 9, 1, 4, 7, 10, 2, 5, 8, 11)));
Panics
This function panics if the dimension of each Vector
yielded
by the given iterator is not equal to the number of rows of
this Matrix
.
let mut matrix = DMatrix::from_vec(3, 2, vec![0, 1, 2, // column 1 3, 4, 5]); // column 2 // The following panics because this matrix can only be extended with 3-dimensional vectors. matrix.extend( vec![Vector2::new(6, 7)]); // too few dimensions!
let mut matrix = DMatrix::from_vec(3, 2, vec![0, 1, 2, // column 1 3, 4, 5]); // column 2 // The following panics because this matrix can only be extended with 3-dimensional vectors. matrix.extend( vec![Vector4::new(6, 7, 8, 9)]); // too few dimensions!
Extends the number of columns of the VecStorage
with elements
from the given iterator.
Panics
This function panics if the number of elements yielded by the
given iterator is not a multiple of the number of rows of the
VecStorage
.
impl<T, R, RV, SV> Extend<Matrix<T, RV, Const<1_usize>, SV>> for VecStorage<T, R, Dynamic> where
T: Scalar,
R: Dim,
RV: Dim,
SV: Storage<T, RV, Const<1_usize>>,
ShapeConstraint: SameNumberOfRows<R, RV>,
impl<T, R, RV, SV> Extend<Matrix<T, RV, Const<1_usize>, SV>> for VecStorage<T, R, Dynamic> where
T: Scalar,
R: Dim,
RV: Dim,
SV: Storage<T, RV, Const<1_usize>>,
ShapeConstraint: SameNumberOfRows<R, RV>,
pub fn extend<I>(&mut self, iter: I) where
I: IntoIterator<Item = Matrix<T, RV, Const<1_usize>, SV>>,
pub fn extend<I>(&mut self, iter: I) where
I: IntoIterator<Item = Matrix<T, RV, Const<1_usize>, SV>>,
Extends the number of columns of the VecStorage
with vectors
from the given iterator.
Panics
This function panics if the number of rows of each Vector
yielded by the iterator is not equal to the number of rows
of this VecStorage
.
Extends the number of rows of the VecStorage
with elements
from the given iterator.