Struct heapless::Vec[][src]

#[repr(transparent)]pub struct Vec<T, N>(_)
where
    N: ArrayLength<T>
;

A fixed capacity Vec

Examples

use heapless::Vec;
use heapless::consts::*;

// A vector with a fixed capacity of 8 elements allocated on the stack
let mut vec = Vec::<_, U8>::new();
vec.push(1);
vec.push(2);

assert_eq!(vec.len(), 2);
assert_eq!(vec[0], 1);

assert_eq!(vec.pop(), Some(2));
assert_eq!(vec.len(), 1);

vec[0] = 7;
assert_eq!(vec[0], 7);

vec.extend([1, 2, 3].iter().cloned());

for x in &vec {
    println!("{}", x);
}
assert_eq!(vec, [7, 1, 2, 3]);

Implementations

impl<T, N> Vec<T, N> where
    N: ArrayLength<T>, 
[src]

pub fn new() -> Self[src]

Constructs a new, empty vector with a fixed capacity of N

Examples

use heapless::Vec;
use heapless::consts::*;

// allocate the vector on the stack
let mut x: Vec<u8, U16> = Vec::new();

// allocate the vector in a static variable
static mut X: Vec<u8, U16> = Vec(heapless::i::Vec::new());

pub fn from_slice(other: &[T]) -> Result<Self, ()> where
    T: Clone
[src]

Constructs a new vector with a fixed capacity of N and fills it with the provided slice.

This is equivalent to the following code:

use heapless::Vec;
use heapless::consts::*;

let mut v: Vec<u8, U16> = Vec::new();
v.extend_from_slice(&[1, 2, 3]).unwrap();

pub fn capacity(&self) -> usize[src]

Returns the maximum number of elements the vector can hold

pub fn clear(&mut self)[src]

Clears the vector, removing all values.

pub fn extend_from_slice(&mut self, other: &[T]) -> Result<(), ()> where
    T: Clone
[src]

Clones and appends all elements in a slice to the Vec.

Iterates over the slice other, clones each element, and then appends it to this Vec. The other vector is traversed in-order.

Examples

use heapless::Vec;
use heapless::consts::*;

let mut vec = Vec::<u8, U8>::new();
vec.push(1).unwrap();
vec.extend_from_slice(&[2, 3, 4]).unwrap();
assert_eq!(*vec, [1, 2, 3, 4]);

pub fn pop(&mut self) -> Option<T>[src]

Removes the last element from a vector and return it, or None if it’s empty

pub fn push(&mut self, item: T) -> Result<(), T>[src]

Appends an item to the back of the collection

Returns back the item if the vector is full

pub fn truncate(&mut self, len: usize)[src]

Shortens the vector, keeping the first len elements and dropping the rest.

pub fn resize(&mut self, new_len: usize, value: T) -> Result<(), ()> where
    T: Clone
[src]

Resizes the Vec in-place so that len is equal to new_len.

If new_len is greater than len, the Vec is extended by the difference, with each additional slot filled with value. If new_len is less than len, the Vec is simply truncated.

See also resize_default.

pub fn resize_default(&mut self, new_len: usize) -> Result<(), ()> where
    T: Clone + Default
[src]

Resizes the Vec in-place so that len is equal to new_len.

If new_len is greater than len, the Vec is extended by the difference, with each additional slot filled with Default::default(). If new_len is less than len, the Vec is simply truncated.

See also resize.

pub unsafe fn set_len(&mut self, new_len: usize)[src]

Forces the length of the vector to new_len.

This is a low-level operation that maintains none of the normal invariants of the type. Normally changing the length of a vector is done using one of the safe operations instead, such as truncate, resize, extend, or clear.

Safety

  • new_len must be less than or equal to capacity().
  • The elements at old_len..new_len must be initialized.

Examples

This method can be useful for situations in which the vector is serving as a buffer for other code, particularly over FFI:

use heapless::Vec;
use heapless::consts::*;

pub fn get_dictionary(&self) -> Option<Vec<u8, U32768>> {
    // Per the FFI method's docs, "32768 bytes is always enough".
    let mut dict = Vec::new();
    let mut dict_length = 0;
    // SAFETY: When `deflateGetDictionary` returns `Z_OK`, it holds that:
    // 1. `dict_length` elements were initialized.
    // 2. `dict_length` <= the capacity (32_768)
    // which makes `set_len` safe to call.
    unsafe {
        // Make the FFI call...
        let r = deflateGetDictionary(self.strm, dict.as_mut_ptr(), &mut dict_length);
        if r == Z_OK {
            // ...and update the length to what was initialized.
            dict.set_len(dict_length);
            Some(dict)
        } else {
            None
        }
    }
}

While the following example is sound, there is a memory leak since the inner vectors were not freed prior to the set_len call:

use core::iter::FromIterator;
use heapless::Vec;
use heapless::consts::*;

let mut vec = Vec::<Vec<u8, U3>, U3>::from_iter(
    [
        Vec::from_iter([1, 0, 0].iter().cloned()),
        Vec::from_iter([0, 1, 0].iter().cloned()),
        Vec::from_iter([0, 0, 1].iter().cloned()),
    ]
    .iter()
    .cloned()
);
// SAFETY:
// 1. `old_len..0` is empty so no elements need to be initialized.
// 2. `0 <= capacity` always holds whatever `capacity` is.
unsafe {
    vec.set_len(0);
}

Normally, here, one would use clear instead to correctly drop the contents and thus not leak memory.

pub fn swap_remove(&mut self, index: usize) -> T[src]

Removes an element from the vector and returns it.

The removed element is replaced by the last element of the vector.

This does not preserve ordering, but is O(1).

Panics

Panics if index is out of bounds.

Examples

use heapless::Vec;
use heapless::consts::*;

let mut v: Vec<_, U8> = Vec::new();
v.push("foo").unwrap();
v.push("bar").unwrap();
v.push("baz").unwrap();
v.push("qux").unwrap();

assert_eq!(v.swap_remove(1), "bar");
assert_eq!(&*v, ["foo", "qux", "baz"]);

assert_eq!(v.swap_remove(0), "foo");
assert_eq!(&*v, ["baz", "qux"]);

pub fn starts_with(&self, needle: &[T]) -> bool where
    T: PartialEq
[src]

Returns true if needle is a prefix of the Vec.

Always returns true if needle is an empty slice.

Examples

use heapless::Vec;
use heapless::consts::*;

let v: Vec<_, U8> = Vec::from_slice(b"abc").unwrap();
assert_eq!(v.starts_with(b""), true);
assert_eq!(v.starts_with(b"ab"), true);
assert_eq!(v.starts_with(b"bc"), false);

pub fn ends_with(&self, needle: &[T]) -> bool where
    T: PartialEq
[src]

Returns true if needle is a suffix of the Vec.

Always returns true if needle is an empty slice.

Examples

use heapless::Vec;
use heapless::consts::*;

let v: Vec<_, U8> = Vec::from_slice(b"abc").unwrap();
assert_eq!(v.ends_with(b""), true);
assert_eq!(v.ends_with(b"ab"), false);
assert_eq!(v.ends_with(b"bc"), true);

Trait Implementations

impl<T, N> AsMut<[T]> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> AsMut<Vec<T, N>> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> AsRef<[T]> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> AsRef<Vec<T, N>> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> Clone for Vec<T, N> where
    N: ArrayLength<T>,
    T: Clone
[src]

impl<T, N> Debug for Vec<T, N> where
    T: Debug,
    N: ArrayLength<T>, 
[src]

impl<T, N> Default for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> Deref for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

type Target = [T]

The resulting type after dereferencing.

impl<T, N> DerefMut for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> Drop for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> Eq for Vec<T, N> where
    N: ArrayLength<T>,
    T: Eq
[src]

impl<'a, T, N> Extend<&'a T> for Vec<T, N> where
    T: 'a + Copy,
    N: ArrayLength<T>, 
[src]

impl<T, N> Extend<T> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> FromIterator<T> for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

impl<T, N> Hash for Vec<T, N> where
    T: Hash,
    N: ArrayLength<T>, 
[src]

impl<T, N> Hash for Vec<T, N> where
    T: Hash,
    N: ArrayLength<T>, 
[src]

impl<'a, T, N> IntoIterator for &'a Vec<T, N> where
    N: ArrayLength<T>, 
[src]

type Item = &'a T

The type of the elements being iterated over.

type IntoIter = Iter<'a, T>

Which kind of iterator are we turning this into?

impl<'a, T, N> IntoIterator for &'a mut Vec<T, N> where
    N: ArrayLength<T>, 
[src]

type Item = &'a mut T

The type of the elements being iterated over.

type IntoIter = IterMut<'a, T>

Which kind of iterator are we turning this into?

impl<T, N> IntoIterator for Vec<T, N> where
    N: ArrayLength<T>, 
[src]

type Item = T

The type of the elements being iterated over.

type IntoIter = IntoIter<T, N>

Which kind of iterator are we turning this into?

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 0]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 1]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 10]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 11]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 12]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 13]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 14]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 15]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 16]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 17]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 18]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 19]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 2]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 20]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 21]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 22]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 23]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 24]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 25]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 26]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 27]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 28]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 29]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 3]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 30]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 31]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 32]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 4]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 5]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 6]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 7]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 8]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B; 9]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a [B]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<&'a mut [B]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 0]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 1]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 10]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 11]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 12]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 13]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 14]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 15]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 16]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 17]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 18]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 19]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 2]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 20]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 21]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 22]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 23]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 24]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 25]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 26]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 27]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 28]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 29]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 3]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 30]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 31]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 32]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 4]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 5]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 6]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 7]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 8]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B; 9]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<'a, 'b, A, B, N> PartialEq<[B]> for Vec<A, N> where
    A: PartialEq<B>,
    N: ArrayLength<A>, 
[src]

impl<A, B, N1, N2> PartialEq<Vec<B, N2>> for Vec<A, N1> where
    N1: ArrayLength<A>,
    N2: ArrayLength<B>,
    A: PartialEq<B>, 
[src]

impl<N> Write for Vec<u8, N> where
    N: ArrayLength<u8>, 
[src]

Auto Trait Implementations

impl<T, N> Send for Vec<T, N> where
    T: Send

impl<T, N> Sync for Vec<T, N> where
    T: Sync

impl<T, N> Unpin for Vec<T, N> where
    <N as ArrayLength<T>>::ArrayType: Unpin

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T> Same<T> for T

type Output = T

Should always be Self

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.