#[repr(C)]
pub struct Vec3<T> { pub x: T, pub y: T, pub z: T, }
Expand description

Vector type suited for 3D spatial coordinates.

Fields

x: Ty: Tz: T

Implementations

Creates a vector from elements.

Broadcasts a single value to all elements of a new vector.

This function is also named splat() in some libraries, or set1() in Intel intrinsics.

“Broadcast” was chosen as the name because it is explicit enough and is the same wording as the description in relevant Intel intrinsics.

assert_eq!(Vec4::broadcast(5), Vec4::new(5,5,5,5));
assert_eq!(Vec4::broadcast(5), Vec4::from(5));

Creates a new vector with all elements set to zero.

assert_eq!(Vec4::zero(), Vec4::new(0,0,0,0));
assert_eq!(Vec4::zero(), Vec4::broadcast(0));
assert_eq!(Vec4::zero(), Vec4::from(0));

Creates a new vector with all elements set to one.

assert_eq!(Vec4::one(), Vec4::new(1,1,1,1));
assert_eq!(Vec4::one(), Vec4::broadcast(1));
assert_eq!(Vec4::one(), Vec4::from(1));

Produces a vector of the first n integers, starting from zero, where n is the number of elements for this vector type.

The iota (ι) function, originating from APL.

See this StackOverflow answer.

This is mostly useful for debugging purposes and tests.

assert_eq!(Vec4::iota(), Vec4::new(0, 1, 2, 3));

Convenience method which returns the number of elements of this vector.

let v = Vec4::new(0,1,2,3);
assert_eq!(v.elem_count(), 4);

Convenience constant representing the number of elements for this vector type.

Converts this into a tuple with the same number of elements by consuming.

Converts this vector into a fixed-size array.

View this vector as an immutable slice.

View this vector as a mutable slice.

Collects the content of a slice into a new vector. Elements are initialized to their default values.

Returns a memberwise-converted copy of this vector, using the given conversion closure.

let v = Vec4::new(0_f32, 1., 1.8, 3.14);
let i = v.map(|x| x.round() as i32);
assert_eq!(i, Vec4::new(0, 1, 2, 3));

Performing LERP on integer vectors by concisely converting them to floats:

let a = Vec4::new(0,1,2,3).map(|x| x as f32);
let b = Vec4::new(2,3,4,5).map(|x| x as f32);
let v = Vec4::lerp(a, b, 0.5_f32).map(|x| x.round() as i32);
assert_eq!(v, Vec4::new(1,2,3,4));

Applies the function f to each element of two vectors, pairwise, and returns the result.

let a = Vec4::<u8>::new(255, 254, 253, 252);
let b = Vec4::<u8>::new(1, 2, 3, 4);
let v = a.map2(b, |a, b| a.wrapping_add(b));
assert_eq!(v, Vec4::zero());
let v = a.map2(b, u8::wrapping_add);
assert_eq!(v, Vec4::zero());

Applies the function f to each element of three vectors, and returns the result.

let a = Vec4::<u8>::new(255, 254, 253, 252);
let b = Vec4::<u8>::new(1, 2, 3, 4);
let c = Vec4::<u8>::new(1, 2, 3, 4);
let v = a.map3(b, c, |a, b, c| a.wrapping_add(b) + c);
assert_eq!(v, c);

Applies the function f to each element of this vector, in-place.

let mut v = Vec4::new(0_u32, 1, 2, 3);
v.apply(|x| x.count_ones());
assert_eq!(v, Vec4::new(0, 1, 1, 2));

Applies the function f to each element of two vectors, pairwise, in-place.

let mut a = Vec4::<u8>::new(255, 254, 253, 252);
let b = Vec4::<u8>::new(1, 2, 3, 4);
a.apply2(b, |a, b| a.wrapping_add(b));
assert_eq!(a, Vec4::zero());
a.apply2(b, u8::wrapping_add);
assert_eq!(a, b);

Applies the function f to each element of three vectors, in-place.

let mut a = Vec4::<u8>::new(255, 254, 253, 252);
let b = Vec4::<u8>::new(1, 2, 3, 4);
let c = Vec4::<u8>::new(1, 2, 3, 4);
a.apply3(b, c, |a, b, c| a.wrapping_add(b) + c);
assert_eq!(a, c);

“Zips” two vectors together into a vector of tuples.

let a = Vec4::<u8>::new(255, 254, 253, 252);
let b = Vec4::<u8>::new(1, 2, 3, 4);
assert_eq!(a.zip(b), Vec4::new((255, 1), (254, 2), (253, 3), (252, 4)));

Returns a memberwise-converted copy of this vector, using AsPrimitive.

Examples
let v = Vec4::new(0_f32, 1., 2., 3.);
let i: Vec4<i32> = v.as_();
assert_eq!(i, Vec4::new(0, 1, 2, 3));
Safety

In Rust versions before 1.45.0, some uses of the as operator were not entirely safe. In particular, it was undefined behavior if a truncated floating point value could not fit in the target integer type (#10184);

let x: u8 = (1.04E+17).as_(); // UB

Returns a memberwise-converted copy of this vector, using NumCast.

let v = Vec4::new(0_f32, 1., 2., 3.);
let i: Vec4<i32> = v.numcast().unwrap();
assert_eq!(i, Vec4::new(0, 1, 2, 3));

Fused multiply-add. Returns self * mul + add, and may be implemented efficiently by the hardware.

The compiler is often able to detect this kind of operation, so generally you don’t need to use it. However, it can make your intent clear.

The name for this method is the one used by the same operation on primitive floating-point types.

let a = Vec4::new(0,1,2,3);
let b = Vec4::new(4,5,6,7);
let c = Vec4::new(8,9,0,1);
assert_eq!(a*b+c, a.mul_add(b, c));

Is any of the elements negative ?

This was intended for checking the validity of extent vectors, but can make sense for other types too.

Are all of the elements positive ?

Compares elements of a and b, and returns the minimum values into a new vector, using total ordering.

let a = Vec4::new(0,1,2,3);
let b = Vec4::new(3,2,1,0);
let m = Vec4::new(0,1,1,0);
assert_eq!(m, Vec4::min(a, b));

Compares elements of a and b, and returns the maximum values into a new vector, using total ordering.

let a = Vec4::new(0,1,2,3);
let b = Vec4::new(3,2,1,0);
let m = Vec4::new(3,2,2,3);
assert_eq!(m, Vec4::max(a, b));

Compares elements of a and b, and returns the minimum values into a new vector, using partial ordering.

let a = Vec4::new(0,1,2,3);
let b = Vec4::new(3,2,1,0);
let m = Vec4::new(0,1,1,0);
assert_eq!(m, Vec4::partial_min(a, b));

Compares elements of a and b, and returns the maximum values into a new vector, using partial ordering.

let a = Vec4::new(0,1,2,3);
let b = Vec4::new(3,2,1,0);
let m = Vec4::new(3,2,2,3);
assert_eq!(m, Vec4::partial_max(a, b));

Returns the element which has the lowest value in this vector, using total ordering.

assert_eq!(-5, Vec4::new(0, 5, -5, 8).reduce_min());

Returns the element which has the highest value in this vector, using total ordering.

assert_eq!(8, Vec4::new(0, 5, -5, 8).reduce_max());

Returns the element which has the lowest value in this vector, using partial ordering.

assert_eq!(-5_f32, Vec4::new(0_f32, 5., -5., 8.).reduce_partial_min());

Returns the element which has the highest value in this vector, using partial ordering.

assert_eq!(8_f32, Vec4::new(0_f32, 5., -5., 8.).reduce_partial_max());

Returns the result of bitwise-AND (&) on all elements of this vector.

assert_eq!(true,  Vec4::new(true, true, true, true).reduce_bitand());
assert_eq!(false, Vec4::new(true, false, true, true).reduce_bitand());
assert_eq!(false, Vec4::new(true, true, true, false).reduce_bitand());

Returns the result of bitwise-OR (|) on all elements of this vector.

assert_eq!(false, Vec4::new(false, false, false, false).reduce_bitor());
assert_eq!(true,  Vec4::new(false, false, true, false).reduce_bitor());

Returns the result of bitwise-XOR (^) on all elements of this vector.

assert_eq!(false, Vec4::new(true, true, true, true).reduce_bitxor());
assert_eq!(true,  Vec4::new(true, false, true, true).reduce_bitxor());

Reduces this vector with the given accumulator closure.

Returns the product of each of this vector’s elements.

assert_eq!(1*2*3*4, Vec4::new(1, 2, 3, 4).product());

Returns the sum of each of this vector’s elements.

assert_eq!(1+2+3+4, Vec4::new(1, 2, 3, 4).sum());

Returns the average of this vector’s elements.

assert_eq!(2.5_f32, Vec4::new(1_f32, 2., 3., 4.).average());

You should avoid using it on u8 vectors, not only because integer overflows cause panics in debug mode, but also because of integer division, the result may not be the one you expect.

// This causes a panic!
let red = Vec4::new(255u8, 1, 0, 0);
let grey_level = red.average();
assert_eq!(grey_level, 128);

You may want to convert the elements to bigger integers (or floating-point) instead:

let red = Vec4::new(255u8, 1, 128, 128);

let red = red.map(|c| c as u16);
let grey_level = red.average() as u8;
assert_eq!(grey_level, 128);

let red = red.map(|c| c as f32);
let grey_level = red.average().round() as u8;
assert_eq!(grey_level, 128);

Returns a new vector which elements are the respective square roots of this vector’s elements.

let v = Vec4::new(1f32, 2f32, 3f32, 4f32);
let s = Vec4::new(1f32, 4f32, 9f32, 16f32);
assert_eq!(v, s.sqrt());

Returns a new vector which elements are the respective reciprocal square roots of this vector’s elements.

let v = Vec4::new(1f32, 0.5f32, 1f32/3f32, 0.25f32);
let s = Vec4::new(1f32, 4f32, 9f32, 16f32);
assert_eq!(v, s.rsqrt());

Returns a new vector which elements are the respective reciprocal of this vector’s elements.

let v = Vec4::new(1f32, 0.5f32, 0.25f32, 0.125f32);
let s = Vec4::new(1f32, 2f32, 4f32, 8f32);
assert_eq!(v, s.recip());
assert_eq!(s, v.recip());

Returns a new vector which elements are rounded to the nearest greater integer.

let v = Vec4::new(0_f32, 1., 1.8, 3.14);
assert_eq!(v.ceil(), Vec4::new(0f32, 1f32, 2f32, 4f32));

Returns a new vector which elements are rounded down to the nearest lower integer.

let v = Vec4::new(0_f32, 1., 1.8, 3.14);
assert_eq!(v.floor(), Vec4::new(0f32, 1f32, 1f32, 3f32));

Returns a new vector which elements are rounded to the nearest integer.

let v = Vec4::new(0_f32, 1., 1.8, 3.14);
assert_eq!(v.round(), Vec4::new(0f32, 1f32, 2f32, 3f32));

Horizontally adds adjacent pairs of elements in self and rhs into a new vector.

let a = Vec4::new(0, 1, 2, 3);
let b = Vec4::new(4, 5, 6, 7);
let h = Vec4::new(0+1, 2+3, 4+5, 6+7);
assert_eq!(h, a.hadd(b));

Compares each element of two vectors with the partial equality test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmpeq(&v), Vec4::new(true, false, true, false));

Compares each element of two vectors with the partial not-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmpne(&v), Vec4::new(false, true, false, true));

Compares each element of two vectors with the partial greater-or-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmpge(&v), Vec4::new(true, true, true, false));

Compares each element of two vectors with the partial greater-than test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmpgt(&v), Vec4::new(false, true, false, true));

Compares each element of two vectors with the partial less-or-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmple(&v), Vec4::new(true, false, true, true));

Compares each element of two vectors with the partial less-than test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.partial_cmplt(&v), Vec4::new(false, false, false, true));

Compares each element of two vectors with the partial equality test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmpeq(&v), Vec4::new(true, false, true, false));

Compares each element of two vectors with the total not-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmpne(&v), Vec4::new(false, true, false, true));

Compares each element of two vectors with the total greater-or-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmpge(&v), Vec4::new(true, true, true, false));

Compares each element of two vectors with the total greater-than test, returning a boolean vector.

let u = Vec4::new(0,2,2,6);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmpgt(&v), Vec4::new(false, true, false, true));

Compares each element of two vectors with the total less-or-equal test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmple(&v), Vec4::new(true, false, true, true));

Compares each element of two vectors with the total less-than test, returning a boolean vector.

let u = Vec4::new(0,2,2,2);
let v = Vec4::new(0,1,2,3);
assert_eq!(u.cmplt(&v), Vec4::new(false, false, false, true));

Returns the linear interpolation of from to to with factor unconstrained. See the Lerp trait.

Same as lerp_unclamped_precise, implemented as a possibly faster but less precise operation. See the Lerp trait.

Returns the linear interpolation of from to to with factor constrained to be between 0 and 1. See the Lerp trait.

Returns the linear interpolation of from to to with factor constrained to be between 0 and 1. See the Lerp trait.

Returns the result of logical AND (&&) on all elements of this vector.

assert_eq!(true,  Vec4::new(true, true, true, true).reduce_and());
assert_eq!(false, Vec4::new(true, false, true, true).reduce_and());
assert_eq!(false, Vec4::new(true, true, true, false).reduce_and());

Returns the result of logical OR (||) on all elements of this vector.

assert_eq!(false, Vec4::new(false, false, false, false).reduce_or());
assert_eq!(true,  Vec4::new(false, false, true, false).reduce_or());

Reduces this vector using total inequality.

assert_eq!(false, Vec4::new(true, true, true, true).reduce_ne());
assert_eq!(true,  Vec4::new(true, false, true, true).reduce_ne());

Dot product between this vector and another.

The squared magnitude of a vector is its spatial length, squared. It is slightly cheaper to compute than magnitude because it avoids a square root.

The magnitude of a vector is its spatial length.

Squared distance between two point vectors. It is slightly cheaper to compute than distance because it avoids a square root.

Distance between two point vectors.

Get a copy of this direction vector such that its length equals 1.

Get a copy of this direction vector such that its length equals 1. If all components approximately zero, None is returned (uses RelativeEq).

Divide this vector’s components such that its length equals 1.

Divide this vector’s components such that its length equals 1, and also returns the previous length.

Get a copy of this direction vector such that its length equals 1, and also returns the length of the original vector.

Is this vector normalized ? (Uses RelativeEq)

Is this vector approximately zero ? (Uses RelativeEq)

Is the magnitude of the vector close to x ? (Uses RelativeEq)

Get the smallest angle, in radians, between two direction vectors.

👎 Deprecated:

Use to_degrees() on the value returned by angle_between() instead

Get the smallest angle, in degrees, between two direction vectors.

The reflection direction for this vector on a surface which normal is given.

The refraction vector for this incident vector, a surface normal and a ratio of indices of refraction (eta).

Orients a vector to point away from a surface as defined by its normal.

Creates a 2D point vector in homogeneous coordinates (sets the last coordinate to 1).

Creates a 2D direction vector in homogeneous coordinates (sets the last coordinate to 0).

Turns a 2D vector into a point vector in homogeneous coordinates (sets the last coordinate to 1).

Turns a 2D vector into a direction vector in homogeneous coordinates (sets the last coordinate to 0).

The cross-product of this vector with another.

On two noncolinear vectors, the result is perpendicular to the plane they define.

The result’s facing direction depends on the handedness of your coordinate system: If we let f be a forward vector and u an up vector, then we have :

  • Right-handed: f.cross(u) points to the right.
  • Left-handed: f.cross(u) points to the left.

There’s a trick to remember this which involves your hand: spread your fingers such that your middle finger points upwards and your index finger points forwards, then your thumb points in the direction of f.cross(u).

The following example demonstrates an identity that is easy to remember.

let i = Vec3::<f32>::unit_x();
let j = Vec3::<f32>::unit_y();
let k = Vec3::<f32>::unit_z();
assert_relative_eq!(i.cross(j), k);

Performs spherical linear interpolation between this vector and another, without implicitly constraining factor to be between 0 and 1.

The vectors are not required to be normalized; their length is also linearly interpolated in the process.

let u = Vec3::<f32>::unit_x();
let v = Vec3::<f32>::unit_y() * 2.;
let slerp = Vec3::slerp(u, v, 0.5);
assert_relative_eq!(slerp.magnitude(), 1.5);
assert_relative_eq!(slerp.x, slerp.y);

Performs spherical linear interpolation between this vector and another, implicitly constraining factor to be between 0 and 1.

The vectors are not required to be normalized; their length is also interpolated in the process.

Get the unit vector which has x set to 1.

Get the unit vector which has y set to 1.

Get the unit vector which has z set to 1.

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has x set to -1.

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has x set to 1.

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has y set to 1.

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has y set to -1.

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has z set to 1 (“forward” in a left-handed coordinate system).

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has z set to -1 (“forward” in a right-handed coordinate system).

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has z set to -1 (“back” in a left-handed coordinate system).

👎 Deprecated since 0.14.0:

This function is opinionated about the semantics of X,Y and Z axii, and should not be used. The mapping of axii (X,Y,Z) to perceived directions (e.g right, up, forward) is not universal at all and varies between libraries, graphics APIs, content creation tools and engines. If you want such helper functions, you should write these yourself as part of the package you’re working on, according to what you know about YOUR current coordinate space.

Get the unit vector which has z set to 1 (“back” in a right-handed coordinate system).

Returns a copy of this vector, with X and Z swapped. This effectively reverses the order of the three elements.

Same as Vec2::from(self), but shorter.

Returns a copy of this vector, with a new X value.

Returns a copy of this vector, with a new Y value.

Returns a copy of this vector, with a new Z value.

Add a W component to this vector such that it becomes a Vec4.

Converts this vector into its #[repr(simd)] counterpart.

Methods from Deref<Target = [T]>

Returns the number of elements in the slice.

Examples
let a = [1, 2, 3];
assert_eq!(a.len(), 3);

Returns true if the slice has a length of 0.

Examples
let a = [1, 2, 3];
assert!(!a.is_empty());

Returns the first element of the slice, or None if it is empty.

Examples
let v = [10, 40, 30];
assert_eq!(Some(&10), v.first());

let w: &[i32] = &[];
assert_eq!(None, w.first());

Returns a mutable pointer to the first element of the slice, or None if it is empty.

Examples
let x = &mut [0, 1, 2];

if let Some(first) = x.first_mut() {
    *first = 5;
}
assert_eq!(x, &[5, 1, 2]);

Returns the first and all the rest of the elements of the slice, or None if it is empty.

Examples
let x = &[0, 1, 2];

if let Some((first, elements)) = x.split_first() {
    assert_eq!(first, &0);
    assert_eq!(elements, &[1, 2]);
}

Returns the first and all the rest of the elements of the slice, or None if it is empty.

Examples
let x = &mut [0, 1, 2];

if let Some((first, elements)) = x.split_first_mut() {
    *first = 3;
    elements[0] = 4;
    elements[1] = 5;
}
assert_eq!(x, &[3, 4, 5]);

Returns the last and all the rest of the elements of the slice, or None if it is empty.

Examples
let x = &[0, 1, 2];

if let Some((last, elements)) = x.split_last() {
    assert_eq!(last, &2);
    assert_eq!(elements, &[0, 1]);
}

Returns the last and all the rest of the elements of the slice, or None if it is empty.

Examples
let x = &mut [0, 1, 2];

if let Some((last, elements)) = x.split_last_mut() {
    *last = 3;
    elements[0] = 4;
    elements[1] = 5;
}
assert_eq!(x, &[4, 5, 3]);

Returns the last element of the slice, or None if it is empty.

Examples
let v = [10, 40, 30];
assert_eq!(Some(&30), v.last());

let w: &[i32] = &[];
assert_eq!(None, w.last());

Returns a mutable pointer to the last item in the slice.

Examples
let x = &mut [0, 1, 2];

if let Some(last) = x.last_mut() {
    *last = 10;
}
assert_eq!(x, &[0, 1, 10]);

Returns a reference to an element or subslice depending on the type of index.

  • If given a position, returns a reference to the element at that position or None if out of bounds.
  • If given a range, returns the subslice corresponding to that range, or None if out of bounds.
Examples
let v = [10, 40, 30];
assert_eq!(Some(&40), v.get(1));
assert_eq!(Some(&[10, 40][..]), v.get(0..2));
assert_eq!(None, v.get(3));
assert_eq!(None, v.get(0..4));

Returns a mutable reference to an element or subslice depending on the type of index (see get) or None if the index is out of bounds.

Examples
let x = &mut [0, 1, 2];

if let Some(elem) = x.get_mut(1) {
    *elem = 42;
}
assert_eq!(x, &[0, 42, 2]);

Returns a reference to an element or subslice, without doing bounds checking.

For a safe alternative see get.

Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used.

Examples
let x = &[1, 2, 4];

unsafe {
    assert_eq!(x.get_unchecked(1), &2);
}

Returns a mutable reference to an element or subslice, without doing bounds checking.

For a safe alternative see get_mut.

Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used.

Examples
let x = &mut [1, 2, 4];

unsafe {
    let elem = x.get_unchecked_mut(1);
    *elem = 13;
}
assert_eq!(x, &[1, 13, 4]);

Returns a raw pointer to the slice’s buffer.

The caller must ensure that the slice outlives the pointer this function returns, or else it will end up pointing to garbage.

The caller must also ensure that the memory the pointer (non-transitively) points to is never written to (except inside an UnsafeCell) using this pointer or any pointer derived from it. If you need to mutate the contents of the slice, use as_mut_ptr.

Modifying the container referenced by this slice may cause its buffer to be reallocated, which would also make any pointers to it invalid.

Examples
let x = &[1, 2, 4];
let x_ptr = x.as_ptr();

unsafe {
    for i in 0..x.len() {
        assert_eq!(x.get_unchecked(i), &*x_ptr.add(i));
    }
}

Returns an unsafe mutable pointer to the slice’s buffer.

The caller must ensure that the slice outlives the pointer this function returns, or else it will end up pointing to garbage.

Modifying the container referenced by this slice may cause its buffer to be reallocated, which would also make any pointers to it invalid.

Examples
let x = &mut [1, 2, 4];
let x_ptr = x.as_mut_ptr();

unsafe {
    for i in 0..x.len() {
        *x_ptr.add(i) += 2;
    }
}
assert_eq!(x, &[3, 4, 6]);

Returns the two raw pointers spanning the slice.

The returned range is half-open, which means that the end pointer points one past the last element of the slice. This way, an empty slice is represented by two equal pointers, and the difference between the two pointers represents the size of the slice.

See as_ptr for warnings on using these pointers. The end pointer requires extra caution, as it does not point to a valid element in the slice.

This function is useful for interacting with foreign interfaces which use two pointers to refer to a range of elements in memory, as is common in C++.

It can also be useful to check if a pointer to an element refers to an element of this slice:

let a = [1, 2, 3];
let x = &a[1] as *const _;
let y = &5 as *const _;

assert!(a.as_ptr_range().contains(&x));
assert!(!a.as_ptr_range().contains(&y));

Returns the two unsafe mutable pointers spanning the slice.

The returned range is half-open, which means that the end pointer points one past the last element of the slice. This way, an empty slice is represented by two equal pointers, and the difference between the two pointers represents the size of the slice.

See as_mut_ptr for warnings on using these pointers. The end pointer requires extra caution, as it does not point to a valid element in the slice.

This function is useful for interacting with foreign interfaces which use two pointers to refer to a range of elements in memory, as is common in C++.

Swaps two elements in the slice.

Arguments
  • a - The index of the first element
  • b - The index of the second element
Panics

Panics if a or b are out of bounds.

Examples
let mut v = ["a", "b", "c", "d", "e"];
v.swap(2, 4);
assert!(v == ["a", "b", "e", "d", "c"]);
🔬 This is a nightly-only experimental API. (slice_swap_unchecked)

Swaps two elements in the slice, without doing bounds checking.

For a safe alternative see swap.

Arguments
  • a - The index of the first element
  • b - The index of the second element
Safety

Calling this method with an out-of-bounds index is undefined behavior. The caller has to ensure that a < self.len() and b < self.len().

Examples
#![feature(slice_swap_unchecked)]

let mut v = ["a", "b", "c", "d"];
// SAFETY: we know that 1 and 3 are both indices of the slice
unsafe { v.swap_unchecked(1, 3) };
assert!(v == ["a", "d", "c", "b"]);

Reverses the order of elements in the slice, in place.

Examples
let mut v = [1, 2, 3];
v.reverse();
assert!(v == [3, 2, 1]);

Returns an iterator over the slice.

Examples
let x = &[1, 2, 4];
let mut iterator = x.iter();

assert_eq!(iterator.next(), Some(&1));
assert_eq!(iterator.next(), Some(&2));
assert_eq!(iterator.next(), Some(&4));
assert_eq!(iterator.next(), None);

Returns an iterator that allows modifying each value.

Examples
let x = &mut [1, 2, 4];
for elem in x.iter_mut() {
    *elem += 2;
}
assert_eq!(x, &[3, 4, 6]);

Returns an iterator over all contiguous windows of length size. The windows overlap. If the slice is shorter than size, the iterator returns no values.

Panics

Panics if size is 0.

Examples
let slice = ['r', 'u', 's', 't'];
let mut iter = slice.windows(2);
assert_eq!(iter.next().unwrap(), &['r', 'u']);
assert_eq!(iter.next().unwrap(), &['u', 's']);
assert_eq!(iter.next().unwrap(), &['s', 't']);
assert!(iter.next().is_none());

If the slice is shorter than size:

let slice = ['f', 'o', 'o'];
let mut iter = slice.windows(4);
assert!(iter.next().is_none());

Returns an iterator over chunk_size elements of the slice at a time, starting at the beginning of the slice.

The chunks are slices and do not overlap. If chunk_size does not divide the length of the slice, then the last chunk will not have length chunk_size.

See chunks_exact for a variant of this iterator that returns chunks of always exactly chunk_size elements, and rchunks for the same iterator but starting at the end of the slice.

Panics

Panics if chunk_size is 0.

Examples
let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.chunks(2);
assert_eq!(iter.next().unwrap(), &['l', 'o']);
assert_eq!(iter.next().unwrap(), &['r', 'e']);
assert_eq!(iter.next().unwrap(), &['m']);
assert!(iter.next().is_none());

Returns an iterator over chunk_size elements of the slice at a time, starting at the beginning of the slice.

The chunks are mutable slices, and do not overlap. If chunk_size does not divide the length of the slice, then the last chunk will not have length chunk_size.

See chunks_exact_mut for a variant of this iterator that returns chunks of always exactly chunk_size elements, and rchunks_mut for the same iterator but starting at the end of the slice.

Panics

Panics if chunk_size is 0.

Examples
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.chunks_mut(2) {
    for elem in chunk.iter_mut() {
        *elem += count;
    }
    count += 1;
}
assert_eq!(v, &[1, 1, 2, 2, 3]);

Returns an iterator over chunk_size elements of the slice at a time, starting at the beginning of the slice.

The chunks are slices and do not overlap. If chunk_size does not divide the length of the slice, then the last up to chunk_size-1 elements will be omitted and can be retrieved from the remainder function of the iterator.

Due to each chunk having exactly chunk_size elements, the compiler can often optimize the resulting code better than in the case of chunks.

See chunks for a variant of this iterator that also returns the remainder as a smaller chunk, and rchunks_exact for the same iterator but starting at the end of the slice.

Panics

Panics if chunk_size is 0.

Examples
let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.chunks_exact(2);
assert_eq!(iter.next().unwrap(), &['l', 'o']);
assert_eq!(iter.next().unwrap(), &['r', 'e']);
assert!(iter.next().is_none());
assert_eq!(iter.remainder(), &['m']);

Returns an iterator over chunk_size elements of the slice at a time, starting at the beginning of the slice.

The chunks are mutable slices, and do not overlap. If chunk_size does not divide the length of the slice, then the last up to chunk_size-1 elements will be omitted and can be retrieved from the into_remainder function of the iterator.

Due to each chunk having exactly chunk_size elements, the compiler can often optimize the resulting code better than in the case of chunks_mut.

See chunks_mut for a variant of this iterator that also returns the remainder as a smaller chunk, and rchunks_exact_mut for the same iterator but starting at the end of the slice.

Panics

Panics if chunk_size is 0.

Examples
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.chunks_exact_mut(2) {
    for elem in chunk.iter_mut() {
        *elem += count;
    }
    count += 1;
}
assert_eq!(v, &[1, 1, 2, 2, 0]);
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, assuming that there’s no remainder.

Safety

This may only be called when

  • The slice splits exactly into N-element chunks (aka self.len() % N == 0).
  • N != 0.
Examples
#![feature(slice_as_chunks)]
let slice: &[char] = &['l', 'o', 'r', 'e', 'm', '!'];
let chunks: &[[char; 1]] =
    // SAFETY: 1-element chunks never have remainder
    unsafe { slice.as_chunks_unchecked() };
assert_eq!(chunks, &[['l'], ['o'], ['r'], ['e'], ['m'], ['!']]);
let chunks: &[[char; 3]] =
    // SAFETY: The slice length (6) is a multiple of 3
    unsafe { slice.as_chunks_unchecked() };
assert_eq!(chunks, &[['l', 'o', 'r'], ['e', 'm', '!']]);

// These would be unsound:
// let chunks: &[[_; 5]] = slice.as_chunks_unchecked() // The slice length is not a multiple of 5
// let chunks: &[[_; 0]] = slice.as_chunks_unchecked() // Zero-length chunks are never allowed
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, starting at the beginning of the slice, and a remainder slice with length strictly less than N.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(slice_as_chunks)]
let slice = ['l', 'o', 'r', 'e', 'm'];
let (chunks, remainder) = slice.as_chunks();
assert_eq!(chunks, &[['l', 'o'], ['r', 'e']]);
assert_eq!(remainder, &['m']);
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, starting at the end of the slice, and a remainder slice with length strictly less than N.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(slice_as_chunks)]
let slice = ['l', 'o', 'r', 'e', 'm'];
let (remainder, chunks) = slice.as_rchunks();
assert_eq!(remainder, &['l']);
assert_eq!(chunks, &[['o', 'r'], ['e', 'm']]);
🔬 This is a nightly-only experimental API. (array_chunks)

Returns an iterator over N elements of the slice at a time, starting at the beginning of the slice.

The chunks are array references and do not overlap. If N does not divide the length of the slice, then the last up to N-1 elements will be omitted and can be retrieved from the remainder function of the iterator.

This method is the const generic equivalent of chunks_exact.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(array_chunks)]
let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.array_chunks();
assert_eq!(iter.next().unwrap(), &['l', 'o']);
assert_eq!(iter.next().unwrap(), &['r', 'e']);
assert!(iter.next().is_none());
assert_eq!(iter.remainder(), &['m']);
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, assuming that there’s no remainder.

Safety

This may only be called when

  • The slice splits exactly into N-element chunks (aka self.len() % N == 0).
  • N != 0.
Examples
#![feature(slice_as_chunks)]
let slice: &mut [char] = &mut ['l', 'o', 'r', 'e', 'm', '!'];
let chunks: &mut [[char; 1]] =
    // SAFETY: 1-element chunks never have remainder
    unsafe { slice.as_chunks_unchecked_mut() };
chunks[0] = ['L'];
assert_eq!(chunks, &[['L'], ['o'], ['r'], ['e'], ['m'], ['!']]);
let chunks: &mut [[char; 3]] =
    // SAFETY: The slice length (6) is a multiple of 3
    unsafe { slice.as_chunks_unchecked_mut() };
chunks[1] = ['a', 'x', '?'];
assert_eq!(slice, &['L', 'o', 'r', 'a', 'x', '?']);

// These would be unsound:
// let chunks: &[[_; 5]] = slice.as_chunks_unchecked_mut() // The slice length is not a multiple of 5
// let chunks: &[[_; 0]] = slice.as_chunks_unchecked_mut() // Zero-length chunks are never allowed
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, starting at the beginning of the slice, and a remainder slice with length strictly less than N.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(slice_as_chunks)]
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

let (chunks, remainder) = v.as_chunks_mut();
remainder[0] = 9;
for chunk in chunks {
    *chunk = [count; 2];
    count += 1;
}
assert_eq!(v, &[1, 1, 2, 2, 9]);
🔬 This is a nightly-only experimental API. (slice_as_chunks)

Splits the slice into a slice of N-element arrays, starting at the end of the slice, and a remainder slice with length strictly less than N.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(slice_as_chunks)]
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

let (remainder, chunks) = v.as_rchunks_mut();
remainder[0] = 9;
for chunk in chunks {
    *chunk = [count; 2];
    count += 1;
}
assert_eq!(v, &[9, 1, 1, 2, 2]);
🔬 This is a nightly-only experimental API. (array_chunks)

Returns an iterator over N elements of the slice at a time, starting at the beginning of the slice.

The chunks are mutable array references and do not overlap. If N does not divide the length of the slice, then the last up to N-1 elements will be omitted and can be retrieved from the into_remainder function of the iterator.

This method is the const generic equivalent of chunks_exact_mut.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(array_chunks)]
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.array_chunks_mut() {
    *chunk = [count; 2];
    count += 1;
}
assert_eq!(v, &[1, 1, 2, 2, 0]);
🔬 This is a nightly-only experimental API. (array_windows)

Returns an iterator over overlapping windows of N elements of a slice, starting at the beginning of the slice.

This is the const generic equivalent of windows.

If N is greater than the size of the slice, it will return no windows.

Panics

Panics if N is 0. This check will most probably get changed to a compile time error before this method gets stabilized.

Examples
#![feature(array_windows)]
let slice = [0, 1, 2, 3];
let mut iter = slice.array_windows();
assert_eq!(iter.next().unwrap(), &[0, 1]);
assert_eq!(iter.next().unwrap(), &[1, 2]);
assert_eq!(iter.next().unwrap(), &[2, 3]);
assert!(iter.next().is_none());

Returns an iterator over chunk_size elements of the slice at a time, starting at the end of the slice.

The chunks are slices and do not overlap. If chunk_size does not divide the length of the slice, then the last chunk will not have length chunk_size.

See rchunks_exact for a variant of this iterator that returns chunks of always exactly chunk_size elements, and chunks for the same iterator but starting at the beginning of the slice.

Panics

Panics if chunk_size is 0.

Examples
let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.rchunks(2);
assert_eq!(iter.next().unwrap(), &['e', 'm']);
assert_eq!(iter.next().unwrap(), &['o', 'r']);
assert_eq!(iter.next().unwrap(), &['l']);
assert!(iter.next().is_none());

Returns an iterator over chunk_size elements of the slice at a time, starting at the end of the slice.

The chunks are mutable slices, and do not overlap. If chunk_size does not divide the length of the slice, then the last chunk will not have length chunk_size.

See rchunks_exact_mut for a variant of this iterator that returns chunks of always exactly chunk_size elements, and chunks_mut for the same iterator but starting at the beginning of the slice.

Panics

Panics if chunk_size is 0.

Examples
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.rchunks_mut(2) {
    for elem in chunk.iter_mut() {
        *elem += count;
    }
    count += 1;
}
assert_eq!(v, &[3, 2, 2, 1, 1]);

Returns an iterator over chunk_size elements of the slice at a time, starting at the end of the slice.

The chunks are slices and do not overlap. If chunk_size does not divide the length of the slice, then the last up to chunk_size-1 elements will be omitted and can be retrieved from the remainder function of the iterator.

Due to each chunk having exactly chunk_size elements, the compiler can often optimize the resulting code better than in the case of chunks.

See rchunks for a variant of this iterator that also returns the remainder as a smaller chunk, and chunks_exact for the same iterator but starting at the beginning of the slice.

Panics

Panics if chunk_size is 0.

Examples
let slice = ['l', 'o', 'r', 'e', 'm'];
let mut iter = slice.rchunks_exact(2);
assert_eq!(iter.next().unwrap(), &['e', 'm']);
assert_eq!(iter.next().unwrap(), &['o', 'r']);
assert!(iter.next().is_none());
assert_eq!(iter.remainder(), &['l']);

Returns an iterator over chunk_size elements of the slice at a time, starting at the end of the slice.

The chunks are mutable slices, and do not overlap. If chunk_size does not divide the length of the slice, then the last up to chunk_size-1 elements will be omitted and can be retrieved from the into_remainder function of the iterator.

Due to each chunk having exactly chunk_size elements, the compiler can often optimize the resulting code better than in the case of chunks_mut.

See rchunks_mut for a variant of this iterator that also returns the remainder as a smaller chunk, and chunks_exact_mut for the same iterator but starting at the beginning of the slice.

Panics

Panics if chunk_size is 0.

Examples
let v = &mut [0, 0, 0, 0, 0];
let mut count = 1;

for chunk in v.rchunks_exact_mut(2) {
    for elem in chunk.iter_mut() {
        *elem += count;
    }
    count += 1;
}
assert_eq!(v, &[0, 2, 2, 1, 1]);
🔬 This is a nightly-only experimental API. (slice_group_by)

Returns an iterator over the slice producing non-overlapping runs of elements using the predicate to separate them.

The predicate is called on two elements following themselves, it means the predicate is called on slice[0] and slice[1] then on slice[1] and slice[2] and so on.

Examples
#![feature(slice_group_by)]

let slice = &[1, 1, 1, 3, 3, 2, 2, 2];

let mut iter = slice.group_by(|a, b| a == b);

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

This method can be used to extract the sorted subslices:

#![feature(slice_group_by)]

let slice = &[1, 1, 2, 3, 2, 3, 2, 3, 4];

let mut iter = slice.group_by(|a, b| a <= b);

assert_eq!(iter.next(), Some(&[1, 1, 2, 3][..]));
assert_eq!(iter.next(), Some(&[2, 3][..]));
assert_eq!(iter.next(), Some(&[2, 3, 4][..]));
assert_eq!(iter.next(), None);
🔬 This is a nightly-only experimental API. (slice_group_by)

Returns an iterator over the slice producing non-overlapping mutable runs of elements using the predicate to separate them.

The predicate is called on two elements following themselves, it means the predicate is called on slice[0] and slice[1] then on slice[1] and slice[2] and so on.

Examples
#![feature(slice_group_by)]

let slice = &mut [1, 1, 1, 3, 3, 2, 2, 2];

let mut iter = slice.group_by_mut(|a, b| a == b);

assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
assert_eq!(iter.next(), Some(&mut [3, 3][..]));
assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
assert_eq!(iter.next(), None);

This method can be used to extract the sorted subslices:

#![feature(slice_group_by)]

let slice = &mut [1, 1, 2, 3, 2, 3, 2, 3, 4];

let mut iter = slice.group_by_mut(|a, b| a <= b);

assert_eq!(iter.next(), Some(&mut [1, 1, 2, 3][..]));
assert_eq!(iter.next(), Some(&mut [2, 3][..]));
assert_eq!(iter.next(), Some(&mut [2, 3, 4][..]));
assert_eq!(iter.next(), None);

Divides one slice into two at an index.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

Panics

Panics if mid > len.

Examples
let v = [1, 2, 3, 4, 5, 6];

{
   let (left, right) = v.split_at(0);
   assert_eq!(left, []);
   assert_eq!(right, [1, 2, 3, 4, 5, 6]);
}

{
    let (left, right) = v.split_at(2);
    assert_eq!(left, [1, 2]);
    assert_eq!(right, [3, 4, 5, 6]);
}

{
    let (left, right) = v.split_at(6);
    assert_eq!(left, [1, 2, 3, 4, 5, 6]);
    assert_eq!(right, []);
}

Divides one mutable slice into two at an index.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

Panics

Panics if mid > len.

Examples
let mut v = [1, 0, 3, 0, 5, 6];
let (left, right) = v.split_at_mut(2);
assert_eq!(left, [1, 0]);
assert_eq!(right, [3, 0, 5, 6]);
left[1] = 2;
right[1] = 4;
assert_eq!(v, [1, 2, 3, 4, 5, 6]);
🔬 This is a nightly-only experimental API. (slice_split_at_unchecked)

Divides one slice into two at an index, without doing bounds checking.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

For a safe alternative see split_at.

Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used. The caller has to ensure that 0 <= mid <= self.len().

Examples
#![feature(slice_split_at_unchecked)]

let v = [1, 2, 3, 4, 5, 6];

unsafe {
   let (left, right) = v.split_at_unchecked(0);
   assert_eq!(left, []);
   assert_eq!(right, [1, 2, 3, 4, 5, 6]);
}

unsafe {
    let (left, right) = v.split_at_unchecked(2);
    assert_eq!(left, [1, 2]);
    assert_eq!(right, [3, 4, 5, 6]);
}

unsafe {
    let (left, right) = v.split_at_unchecked(6);
    assert_eq!(left, [1, 2, 3, 4, 5, 6]);
    assert_eq!(right, []);
}
🔬 This is a nightly-only experimental API. (slice_split_at_unchecked)

Divides one mutable slice into two at an index, without doing bounds checking.

The first will contain all indices from [0, mid) (excluding the index mid itself) and the second will contain all indices from [mid, len) (excluding the index len itself).

For a safe alternative see split_at_mut.

Safety

Calling this method with an out-of-bounds index is undefined behavior even if the resulting reference is not used. The caller has to ensure that 0 <= mid <= self.len().

Examples
#![feature(slice_split_at_unchecked)]

let mut v = [1, 0, 3, 0, 5, 6];
// scoped to restrict the lifetime of the borrows
unsafe {
    let (left, right) = v.split_at_mut_unchecked(2);
    assert_eq!(left, [1, 0]);
    assert_eq!(right, [3, 0, 5, 6]);
    left[1] = 2;
    right[1] = 4;
}
assert_eq!(v, [1, 2, 3, 4, 5, 6]);
🔬 This is a nightly-only experimental API. (split_array)

Divides one slice into an array and a remainder slice at an index.

The array will contain all indices from [0, N) (excluding the index N itself) and the slice will contain all indices from [N, len) (excluding the index len itself).

Panics

Panics if N > len.

Examples
#![feature(split_array)]

let v = &[1, 2, 3, 4, 5, 6][..];

{
   let (left, right) = v.split_array_ref::<0>();
   assert_eq!(left, &[]);
   assert_eq!(right, [1, 2, 3, 4, 5, 6]);
}

{
    let (left, right) = v.split_array_ref::<2>();
    assert_eq!(left, &[1, 2]);
    assert_eq!(right, [3, 4, 5, 6]);
}

{
    let (left, right) = v.split_array_ref::<6>();
    assert_eq!(left, &[1, 2, 3, 4, 5, 6]);
    assert_eq!(right, []);
}
🔬 This is a nightly-only experimental API. (split_array)

Divides one mutable slice into an array and a remainder slice at an index.

The array will contain all indices from [0, N) (excluding the index N itself) and the slice will contain all indices from [N, len) (excluding the index len itself).

Panics

Panics if N > len.

Examples
#![feature(split_array)]

let mut v = &mut [1, 0, 3, 0, 5, 6][..];
let (left, right) = v.split_array_mut::<2>();
assert_eq!(left, &mut [1, 0]);
assert_eq!(right, [3, 0, 5, 6]);
left[1] = 2;
right[1] = 4;
assert_eq!(v, [1, 2, 3, 4, 5, 6]);
🔬 This is a nightly-only experimental API. (split_array)

Divides one slice into an array and a remainder slice at an index from the end.

The slice will contain all indices from [0, len - N) (excluding the index len - N itself) and the array will contain all indices from [len - N, len) (excluding the index len itself).

Panics

Panics if N > len.

Examples
#![feature(split_array)]

let v = &[1, 2, 3, 4, 5, 6][..];

{
   let (left, right) = v.rsplit_array_ref::<0>();
   assert_eq!(left, [1, 2, 3, 4, 5, 6]);
   assert_eq!(right, &[]);
}

{
    let (left, right) = v.rsplit_array_ref::<2>();
    assert_eq!(left, [1, 2, 3, 4]);
    assert_eq!(right, &[5, 6]);
}

{
    let (left, right) = v.rsplit_array_ref::<6>();
    assert_eq!(left, []);
    assert_eq!(right, &[1, 2, 3, 4, 5, 6]);
}
🔬 This is a nightly-only experimental API. (split_array)

Divides one mutable slice into an array and a remainder slice at an index from the end.

The slice will contain all indices from [0, len - N) (excluding the index N itself) and the array will contain all indices from [len - N, len) (excluding the index len itself).

Panics

Panics if N > len.

Examples
#![feature(split_array)]

let mut v = &mut [1, 0, 3, 0, 5, 6][..];
let (left, right) = v.rsplit_array_mut::<4>();
assert_eq!(left, [1, 0]);
assert_eq!(right, &mut [3, 0, 5, 6]);
left[1] = 2;
right[1] = 4;
assert_eq!(v, [1, 2, 3, 4, 5, 6]);

Returns an iterator over subslices separated by elements that match pred. The matched element is not contained in the subslices.

Examples
let slice = [10, 40, 33, 20];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10, 40]);
assert_eq!(iter.next().unwrap(), &[20]);
assert!(iter.next().is_none());

If the first element is matched, an empty slice will be the first item returned by the iterator. Similarly, if the last element in the slice is matched, an empty slice will be the last item returned by the iterator:

let slice = [10, 40, 33];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10, 40]);
assert_eq!(iter.next().unwrap(), &[]);
assert!(iter.next().is_none());

If two matched elements are directly adjacent, an empty slice will be present between them:

let slice = [10, 6, 33, 20];
let mut iter = slice.split(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10]);
assert_eq!(iter.next().unwrap(), &[]);
assert_eq!(iter.next().unwrap(), &[20]);
assert!(iter.next().is_none());

Returns an iterator over mutable subslices separated by elements that match pred. The matched element is not contained in the subslices.

Examples
let mut v = [10, 40, 30, 20, 60, 50];

for group in v.split_mut(|num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(v, [1, 40, 30, 1, 60, 1]);

Returns an iterator over subslices separated by elements that match pred. The matched element is contained in the end of the previous subslice as a terminator.

Examples
let slice = [10, 40, 33, 20];
let mut iter = slice.split_inclusive(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[10, 40, 33]);
assert_eq!(iter.next().unwrap(), &[20]);
assert!(iter.next().is_none());

If the last element of the slice is matched, that element will be considered the terminator of the preceding slice. That slice will be the last item returned by the iterator.

let slice = [3, 10, 40, 33];
let mut iter = slice.split_inclusive(|num| num % 3 == 0);

assert_eq!(iter.next().unwrap(), &[3]);
assert_eq!(iter.next().unwrap(), &[10, 40, 33]);
assert!(iter.next().is_none());

Returns an iterator over mutable subslices separated by elements that match pred. The matched element is contained in the previous subslice as a terminator.

Examples
let mut v = [10, 40, 30, 20, 60, 50];

for group in v.split_inclusive_mut(|num| *num % 3 == 0) {
    let terminator_idx = group.len()-1;
    group[terminator_idx] = 1;
}
assert_eq!(v, [10, 40, 1, 20, 1, 1]);

Returns an iterator over subslices separated by elements that match pred, starting at the end of the slice and working backwards. The matched element is not contained in the subslices.

Examples
let slice = [11, 22, 33, 0, 44, 55];
let mut iter = slice.rsplit(|num| *num == 0);

assert_eq!(iter.next().unwrap(), &[44, 55]);
assert_eq!(iter.next().unwrap(), &[11, 22, 33]);
assert_eq!(iter.next(), None);

As with split(), if the first or last element is matched, an empty slice will be the first (or last) item returned by the iterator.

let v = &[0, 1, 1, 2, 3, 5, 8];
let mut it = v.rsplit(|n| *n % 2 == 0);
assert_eq!(it.next().unwrap(), &[]);
assert_eq!(it.next().unwrap(), &[3, 5]);
assert_eq!(it.next().unwrap(), &[1, 1]);
assert_eq!(it.next().unwrap(), &[]);
assert_eq!(it.next(), None);

Returns an iterator over mutable subslices separated by elements that match pred, starting at the end of the slice and working backwards. The matched element is not contained in the subslices.

Examples
let mut v = [100, 400, 300, 200, 600, 500];

let mut count = 0;
for group in v.rsplit_mut(|num| *num % 3 == 0) {
    count += 1;
    group[0] = count;
}
assert_eq!(v, [3, 400, 300, 2, 600, 1]);

Returns an iterator over subslices separated by elements that match pred, limited to returning at most n items. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

Print the slice split once by numbers divisible by 3 (i.e., [10, 40], [20, 60, 50]):

let v = [10, 40, 30, 20, 60, 50];

for group in v.splitn(2, |num| *num % 3 == 0) {
    println!("{:?}", group);
}

Returns an iterator over subslices separated by elements that match pred, limited to returning at most n items. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples
let mut v = [10, 40, 30, 20, 60, 50];

for group in v.splitn_mut(2, |num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(v, [1, 40, 30, 1, 60, 50]);

Returns an iterator over subslices separated by elements that match pred limited to returning at most n items. This starts at the end of the slice and works backwards. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples

Print the slice split once, starting from the end, by numbers divisible by 3 (i.e., [50], [10, 40, 30, 20]):

let v = [10, 40, 30, 20, 60, 50];

for group in v.rsplitn(2, |num| *num % 3 == 0) {
    println!("{:?}", group);
}

Returns an iterator over subslices separated by elements that match pred limited to returning at most n items. This starts at the end of the slice and works backwards. The matched element is not contained in the subslices.

The last element returned, if any, will contain the remainder of the slice.

Examples
let mut s = [10, 40, 30, 20, 60, 50];

for group in s.rsplitn_mut(2, |num| *num % 3 == 0) {
    group[0] = 1;
}
assert_eq!(s, [1, 40, 30, 20, 60, 1]);

Returns true if the slice contains an element with the given value.

Examples
let v = [10, 40, 30];
assert!(v.contains(&30));
assert!(!v.contains(&50));

If you do not have a &T, but some other value that you can compare with one (for example, String implements PartialEq<str>), you can use iter().any:

let v = [String::from("hello"), String::from("world")]; // slice of `String`
assert!(v.iter().any(|e| e == "hello")); // search with `&str`
assert!(!v.iter().any(|e| e == "hi"));

Returns true if needle is a prefix of the slice.

Examples
let v = [10, 40, 30];
assert!(v.starts_with(&[10]));
assert!(v.starts_with(&[10, 40]));
assert!(!v.starts_with(&[50]));
assert!(!v.starts_with(&[10, 50]));

Always returns true if needle is an empty slice:

let v = &[10, 40, 30];
assert!(v.starts_with(&[]));
let v: &[u8] = &[];
assert!(v.starts_with(&[]));

Returns true if needle is a suffix of the slice.

Examples
let v = [10, 40, 30];
assert!(v.ends_with(&[30]));
assert!(v.ends_with(&[40, 30]));
assert!(!v.ends_with(&[50]));
assert!(!v.ends_with(&[50, 30]));

Always returns true if needle is an empty slice:

let v = &[10, 40, 30];
assert!(v.ends_with(&[]));
let v: &[u8] = &[];
assert!(v.ends_with(&[]));

Returns a subslice with the prefix removed.

If the slice starts with prefix, returns the subslice after the prefix, wrapped in Some. If prefix is empty, simply returns the original slice.

If the slice does not start with prefix, returns None.

Examples
let v = &[10, 40, 30];
assert_eq!(v.strip_prefix(&[10]), Some(&[40, 30][..]));
assert_eq!(v.strip_prefix(&[10, 40]), Some(&[30][..]));
assert_eq!(v.strip_prefix(&[50]), None);
assert_eq!(v.strip_prefix(&[10, 50]), None);

let prefix : &str = "he";
assert_eq!(b"hello".strip_prefix(prefix.as_bytes()),
           Some(b"llo".as_ref()));

Returns a subslice with the suffix removed.

If the slice ends with suffix, returns the subslice before the suffix, wrapped in Some. If suffix is empty, simply returns the original slice.

If the slice does not end with suffix, returns None.

Examples
let v = &[10, 40, 30];
assert_eq!(v.strip_suffix(&[30]), Some(&[10, 40][..]));
assert_eq!(v.strip_suffix(&[40, 30]), Some(&[10][..]));
assert_eq!(v.strip_suffix(&[50]), None);
assert_eq!(v.strip_suffix(&[50, 30]), None);

Binary searches this sorted slice for a given element.

If the value is found then Result::Ok is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. The index is chosen deterministically, but is subject to change in future versions of Rust. If the value is not found then Result::Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also binary_search_by, binary_search_by_key, and partition_point.

Examples

Looks up a series of four elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];

assert_eq!(s.binary_search(&13),  Ok(9));
assert_eq!(s.binary_search(&4),   Err(7));
assert_eq!(s.binary_search(&100), Err(13));
let r = s.binary_search(&1);
assert!(match r { Ok(1..=4) => true, _ => false, });

If you want to insert an item to a sorted vector, while maintaining sort order:

let mut s = vec![0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];
let num = 42;
let idx = s.binary_search(&num).unwrap_or_else(|x| x);
s.insert(idx, num);
assert_eq!(s, [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 42, 55]);

Binary searches this sorted slice with a comparator function.

The comparator function should implement an order consistent with the sort order of the underlying slice, returning an order code that indicates whether its argument is Less, Equal or Greater the desired target.

If the value is found then Result::Ok is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. The index is chosen deterministically, but is subject to change in future versions of Rust. If the value is not found then Result::Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also binary_search, binary_search_by_key, and partition_point.

Examples

Looks up a series of four elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [0, 1, 1, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55];

let seek = 13;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Ok(9));
let seek = 4;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(7));
let seek = 100;
assert_eq!(s.binary_search_by(|probe| probe.cmp(&seek)), Err(13));
let seek = 1;
let r = s.binary_search_by(|probe| probe.cmp(&seek));
assert!(match r { Ok(1..=4) => true, _ => false, });

Binary searches this sorted slice with a key extraction function.

Assumes that the slice is sorted by the key, for instance with sort_by_key using the same key extraction function.

If the value is found then Result::Ok is returned, containing the index of the matching element. If there are multiple matches, then any one of the matches could be returned. The index is chosen deterministically, but is subject to change in future versions of Rust. If the value is not found then Result::Err is returned, containing the index where a matching element could be inserted while maintaining sorted order.

See also binary_search, binary_search_by, and partition_point.

Examples

Looks up a series of four elements in a slice of pairs sorted by their second elements. The first is found, with a uniquely determined position; the second and third are not found; the fourth could match any position in [1, 4].

let s = [(0, 0), (2, 1), (4, 1), (5, 1), (3, 1),
         (1, 2), (2, 3), (4, 5), (5, 8), (3, 13),
         (1, 21), (2, 34), (4, 55)];

assert_eq!(s.binary_search_by_key(&13, |&(a, b)| b),  Ok(9));
assert_eq!(s.binary_search_by_key(&4, |&(a, b)| b),   Err(7));
assert_eq!(s.binary_search_by_key(&100, |&(a, b)| b), Err(13));
let r = s.binary_search_by_key(&1, |&(a, b)| b);
assert!(match r { Ok(1..=4) => true, _ => false, });

Sorts the slice, but might not preserve the order of equal elements.

This sort is unstable (i.e., may reorder equal elements), in-place (i.e., does not allocate), and O(n * log(n)) worst-case.

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

It is typically faster than stable sorting, except in a few special cases, e.g., when the slice consists of several concatenated sorted sequences.

Examples
let mut v = [-5, 4, 1, -3, 2];

v.sort_unstable();
assert!(v == [-5, -3, 1, 2, 4]);

Sorts the slice with a comparator function, but might not preserve the order of equal elements.

This sort is unstable (i.e., may reorder equal elements), in-place (i.e., does not allocate), and O(n * log(n)) worst-case.

The comparator function must define a total ordering for the elements in the slice. If the ordering is not total, the order of the elements is unspecified. An order is a total order if it is (for all a, b and c):

  • total and antisymmetric: exactly one of a < b, a == b or a > b is true, and
  • transitive, a < b and b < c implies a < c. The same must hold for both == and >.

For example, while f64 doesn’t implement Ord because NaN != NaN, we can use partial_cmp as our sort function when we know the slice doesn’t contain a NaN.

let mut floats = [5f64, 4.0, 1.0, 3.0, 2.0];
floats.sort_unstable_by(|a, b| a.partial_cmp(b).unwrap());
assert_eq!(floats, [1.0, 2.0, 3.0, 4.0, 5.0]);
Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

It is typically faster than stable sorting, except in a few special cases, e.g., when the slice consists of several concatenated sorted sequences.

Examples
let mut v = [5, 4, 1, 3, 2];
v.sort_unstable_by(|a, b| a.cmp(b));
assert!(v == [1, 2, 3, 4, 5]);

// reverse sorting
v.sort_unstable_by(|a, b| b.cmp(a));
assert!(v == [5, 4, 3, 2, 1]);

Sorts the slice with a key extraction function, but might not preserve the order of equal elements.

This sort is unstable (i.e., may reorder equal elements), in-place (i.e., does not allocate), and O(m * n * log(n)) worst-case, where the key function is O(m).

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

Due to its key calling strategy, sort_unstable_by_key is likely to be slower than sort_by_cached_key in cases where the key function is expensive.

Examples
let mut v = [-5i32, 4, 1, -3, 2];

v.sort_unstable_by_key(|k| k.abs());
assert!(v == [1, 2, -3, 4, -5]);

Reorder the slice such that the element at index is at its final sorted position.

This reordering has the additional property that any value at position i < index will be less than or equal to any value at a position j > index. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position index), in-place (i.e. does not allocate), and O(n) worst-case. This function is also/ known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index.

Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for sort_unstable.

Panics

Panics when index >= len(), meaning it always panics on empty slices.

Examples
let mut v = [-5i32, 4, 1, -3, 2];

// Find the median
v.select_nth_unstable(2);

// We are only guaranteed the slice will be one of the following, based on the way we sort
// about the specified index.
assert!(v == [-3, -5, 1, 2, 4] ||
        v == [-5, -3, 1, 2, 4] ||
        v == [-3, -5, 1, 4, 2] ||
        v == [-5, -3, 1, 4, 2]);

Reorder the slice with a comparator function such that the element at index is at its final sorted position.

This reordering has the additional property that any value at position i < index will be less than or equal to any value at a position j > index using the comparator function. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position index), in-place (i.e. does not allocate), and O(n) worst-case. This function is also known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index, using the provided comparator function.

Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for sort_unstable.

Panics

Panics when index >= len(), meaning it always panics on empty slices.

Examples
let mut v = [-5i32, 4, 1, -3, 2];

// Find the median as if the slice were sorted in descending order.
v.select_nth_unstable_by(2, |a, b| b.cmp(a));

// We are only guaranteed the slice will be one of the following, based on the way we sort
// about the specified index.
assert!(v == [2, 4, 1, -5, -3] ||
        v == [2, 4, 1, -3, -5] ||
        v == [4, 2, 1, -5, -3] ||
        v == [4, 2, 1, -3, -5]);

Reorder the slice with a key extraction function such that the element at index is at its final sorted position.

This reordering has the additional property that any value at position i < index will be less than or equal to any value at a position j > index using the key extraction function. Additionally, this reordering is unstable (i.e. any number of equal elements may end up at position index), in-place (i.e. does not allocate), and O(n) worst-case. This function is also known as “kth element” in other libraries. It returns a triplet of the following values: all elements less than the one at the given index, the value at the given index, and all elements greater than the one at the given index, using the provided key extraction function.

Current implementation

The current algorithm is based on the quickselect portion of the same quicksort algorithm used for sort_unstable.

Panics

Panics when index >= len(), meaning it always panics on empty slices.

Examples
let mut v = [-5i32, 4, 1, -3, 2];

// Return the median as if the array were sorted according to absolute value.
v.select_nth_unstable_by_key(2, |a| a.abs());

// We are only guaranteed the slice will be one of the following, based on the way we sort
// about the specified index.
assert!(v == [1, 2, -3, 4, -5] ||
        v == [1, 2, -3, -5, 4] ||
        v == [2, 1, -3, 4, -5] ||
        v == [2, 1, -3, -5, 4]);
🔬 This is a nightly-only experimental API. (slice_partition_dedup)

Moves all consecutive repeated elements to the end of the slice according to the PartialEq trait implementation.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

If the slice is sorted, the first returned slice contains no duplicates.

Examples
#![feature(slice_partition_dedup)]

let mut slice = [1, 2, 2, 3, 3, 2, 1, 1];

let (dedup, duplicates) = slice.partition_dedup();

assert_eq!(dedup, [1, 2, 3, 2, 1]);
assert_eq!(duplicates, [2, 3, 1]);
🔬 This is a nightly-only experimental API. (slice_partition_dedup)

Moves all but the first of consecutive elements to the end of the slice satisfying a given equality relation.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

The same_bucket function is passed references to two elements from the slice and must determine if the elements compare equal. The elements are passed in opposite order from their order in the slice, so if same_bucket(a, b) returns true, a is moved at the end of the slice.

If the slice is sorted, the first returned slice contains no duplicates.

Examples
#![feature(slice_partition_dedup)]

let mut slice = ["foo", "Foo", "BAZ", "Bar", "bar", "baz", "BAZ"];

let (dedup, duplicates) = slice.partition_dedup_by(|a, b| a.eq_ignore_ascii_case(b));

assert_eq!(dedup, ["foo", "BAZ", "Bar", "baz"]);
assert_eq!(duplicates, ["bar", "Foo", "BAZ"]);
🔬 This is a nightly-only experimental API. (slice_partition_dedup)

Moves all but the first of consecutive elements to the end of the slice that resolve to the same key.

Returns two slices. The first contains no consecutive repeated elements. The second contains all the duplicates in no specified order.

If the slice is sorted, the first returned slice contains no duplicates.

Examples
#![feature(slice_partition_dedup)]

let mut slice = [10, 20, 21, 30, 30, 20, 11, 13];

let (dedup, duplicates) = slice.partition_dedup_by_key(|i| *i / 10);

assert_eq!(dedup, [10, 20, 30, 20, 11]);
assert_eq!(duplicates, [21, 30, 13]);

Rotates the slice in-place such that the first mid elements of the slice move to the end while the last self.len() - mid elements move to the front. After calling rotate_left, the element previously at index mid will become the first element in the slice.

Panics

This function will panic if mid is greater than the length of the slice. Note that mid == self.len() does not panic and is a no-op rotation.

Complexity

Takes linear (in self.len()) time.

Examples
let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
a.rotate_left(2);
assert_eq!(a, ['c', 'd', 'e', 'f', 'a', 'b']);

Rotating a subslice:

let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
a[1..5].rotate_left(1);
assert_eq!(a, ['a', 'c', 'd', 'e', 'b', 'f']);

Rotates the slice in-place such that the first self.len() - k elements of the slice move to the end while the last k elements move to the front. After calling rotate_right, the element previously at index self.len() - k will become the first element in the slice.

Panics

This function will panic if k is greater than the length of the slice. Note that k == self.len() does not panic and is a no-op rotation.

Complexity

Takes linear (in self.len()) time.

Examples
let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
a.rotate_right(2);
assert_eq!(a, ['e', 'f', 'a', 'b', 'c', 'd']);

Rotate a subslice:

let mut a = ['a', 'b', 'c', 'd', 'e', 'f'];
a[1..5].rotate_right(1);
assert_eq!(a, ['a', 'e', 'b', 'c', 'd', 'f']);

Fills self with elements by cloning value.

Examples
let mut buf = vec![0; 10];
buf.fill(1);
assert_eq!(buf, vec![1; 10]);

Fills self with elements returned by calling a closure repeatedly.

This method uses a closure to create new values. If you’d rather Clone a given value, use fill. If you want to use the Default trait to generate values, you can pass Default::default as the argument.

Examples
let mut buf = vec![1; 10];
buf.fill_with(Default::default);
assert_eq!(buf, vec![0; 10]);

Copies the elements from src into self.

The length of src must be the same as self.

Panics

This function will panic if the two slices have different lengths.

Examples

Cloning two elements from a slice into another:

let src = [1, 2, 3, 4];
let mut dst = [0, 0];

// Because the slices have to be the same length,
// we slice the source slice from four elements
// to two. It will panic if we don't do this.
dst.clone_from_slice(&src[2..]);

assert_eq!(src, [1, 2, 3, 4]);
assert_eq!(dst, [3, 4]);

Rust enforces that there can only be one mutable reference with no immutable references to a particular piece of data in a particular scope. Because of this, attempting to use clone_from_slice on a single slice will result in a compile failure:

let mut slice = [1, 2, 3, 4, 5];

slice[..2].clone_from_slice(&slice[3..]); // compile fail!

To work around this, we can use split_at_mut to create two distinct sub-slices from a slice:

let mut slice = [1, 2, 3, 4, 5];

{
    let (left, right) = slice.split_at_mut(2);
    left.clone_from_slice(&right[1..]);
}

assert_eq!(slice, [4, 5, 3, 4, 5]);

Copies all elements from src into self, using a memcpy.

The length of src must be the same as self.

If T does not implement Copy, use clone_from_slice.

Panics

This function will panic if the two slices have different lengths.

Examples

Copying two elements from a slice into another:

let src = [1, 2, 3, 4];
let mut dst = [0, 0];

// Because the slices have to be the same length,
// we slice the source slice from four elements
// to two. It will panic if we don't do this.
dst.copy_from_slice(&src[2..]);

assert_eq!(src, [1, 2, 3, 4]);
assert_eq!(dst, [3, 4]);

Rust enforces that there can only be one mutable reference with no immutable references to a particular piece of data in a particular scope. Because of this, attempting to use copy_from_slice on a single slice will result in a compile failure:

let mut slice = [1, 2, 3, 4, 5];

slice[..2].copy_from_slice(&slice[3..]); // compile fail!

To work around this, we can use split_at_mut to create two distinct sub-slices from a slice:

let mut slice = [1, 2, 3, 4, 5];

{
    let (left, right) = slice.split_at_mut(2);
    left.copy_from_slice(&right[1..]);
}

assert_eq!(slice, [4, 5, 3, 4, 5]);

Copies elements from one part of the slice to another part of itself, using a memmove.

src is the range within self to copy from. dest is the starting index of the range within self to copy to, which will have the same length as src. The two ranges may overlap. The ends of the two ranges must be less than or equal to self.len().

Panics

This function will panic if either range exceeds the end of the slice, or if the end of src is before the start.

Examples

Copying four bytes within a slice:

let mut bytes = *b"Hello, World!";

bytes.copy_within(1..5, 8);

assert_eq!(&bytes, b"Hello, Wello!");

Swaps all elements in self with those in other.

The length of other must be the same as self.

Panics

This function will panic if the two slices have different lengths.

Example

Swapping two elements across slices:

let mut slice1 = [0, 0];
let mut slice2 = [1, 2, 3, 4];

slice1.swap_with_slice(&mut slice2[2..]);

assert_eq!(slice1, [3, 4]);
assert_eq!(slice2, [1, 2, 0, 0]);

Rust enforces that there can only be one mutable reference to a particular piece of data in a particular scope. Because of this, attempting to use swap_with_slice on a single slice will result in a compile failure:

let mut slice = [1, 2, 3, 4, 5];
slice[..2].swap_with_slice(&mut slice[3..]); // compile fail!

To work around this, we can use split_at_mut to create two distinct mutable sub-slices from a slice:

let mut slice = [1, 2, 3, 4, 5];

{
    let (left, right) = slice.split_at_mut(2);
    left.swap_with_slice(&mut right[1..]);
}

assert_eq!(slice, [4, 5, 3, 1, 2]);

Transmute the slice to a slice of another type, ensuring alignment of the types is maintained.

This method splits the slice into three distinct slices: prefix, correctly aligned middle slice of a new type, and the suffix slice. The method may make the middle slice the greatest length possible for a given type and input slice, but only your algorithm’s performance should depend on that, not its correctness. It is permissible for all of the input data to be returned as the prefix or suffix slice.

This method has no purpose when either input element T or output element U are zero-sized and will return the original slice without splitting anything.

Safety

This method is essentially a transmute with respect to the elements in the returned middle slice, so all the usual caveats pertaining to transmute::<T, U> also apply here.

Examples

Basic usage:

unsafe {
    let bytes: [u8; 7] = [1, 2, 3, 4, 5, 6, 7];
    let (prefix, shorts, suffix) = bytes.align_to::<u16>();
    // less_efficient_algorithm_for_bytes(prefix);
    // more_efficient_algorithm_for_aligned_shorts(shorts);
    // less_efficient_algorithm_for_bytes(suffix);
}

Transmute the slice to a slice of another type, ensuring alignment of the types is maintained.

This method splits the slice into three distinct slices: prefix, correctly aligned middle slice of a new type, and the suffix slice. The method may make the middle slice the greatest length possible for a given type and input slice, but only your algorithm’s performance should depend on that, not its correctness. It is permissible for all of the input data to be returned as the prefix or suffix slice.

This method has no purpose when either input element T or output element U are zero-sized and will return the original slice without splitting anything.

Safety

This method is essentially a transmute with respect to the elements in the returned middle slice, so all the usual caveats pertaining to transmute::<T, U> also apply here.

Examples

Basic usage:

unsafe {
    let mut bytes: [u8; 7] = [1, 2, 3, 4, 5, 6, 7];
    let (prefix, shorts, suffix) = bytes.align_to_mut::<u16>();
    // less_efficient_algorithm_for_bytes(prefix);
    // more_efficient_algorithm_for_aligned_shorts(shorts);
    // less_efficient_algorithm_for_bytes(suffix);
}
🔬 This is a nightly-only experimental API. (portable_simd)

Split a slice into a prefix, a middle of aligned SIMD types, and a suffix.

This is a safe wrapper around slice::align_to, so has the same weak postconditions as that method. You’re only assured that self.len() == prefix.len() + middle.len() * LANES + suffix.len().

Notably, all of the following are possible:

  • prefix.len() >= LANES.
  • middle.is_empty() despite self.len() >= 3 * LANES.
  • suffix.len() >= LANES.

That said, this is a safe method, so if you’re only writing safe code, then this can at most cause incorrect logic, not unsoundness.

Panics

This will panic if the size of the SIMD type is different from LANES times that of the scalar.

At the time of writing, the trait restrictions on Simd<T, LANES> keeps that from ever happening, as only power-of-two numbers of lanes are supported. It’s possible that, in the future, those restrictions might be lifted in a way that would make it possible to see panics from this method for something like LANES == 3.

Examples
#![feature(portable_simd)]

let short = &[1, 2, 3];
let (prefix, middle, suffix) = short.as_simd::<4>();
assert_eq!(middle, []); // Not enough elements for anything in the middle

// They might be split in any possible way between prefix and suffix
let it = prefix.iter().chain(suffix).copied();
assert_eq!(it.collect::<Vec<_>>(), vec![1, 2, 3]);

fn basic_simd_sum(x: &[f32]) -> f32 {
    use std::ops::Add;
    use std::simd::f32x4;
    let (prefix, middle, suffix) = x.as_simd();
    let sums = f32x4::from_array([
        prefix.iter().copied().sum(),
        0.0,
        0.0,
        suffix.iter().copied().sum(),
    ]);
    let sums = middle.iter().copied().fold(sums, f32x4::add);
    sums.horizontal_sum()
}

let numbers: Vec<f32> = (1..101).map(|x| x as _).collect();
assert_eq!(basic_simd_sum(&numbers[1..99]), 4949.0);
🔬 This is a nightly-only experimental API. (portable_simd)

Split a slice into a prefix, a middle of aligned SIMD types, and a suffix.

This is a safe wrapper around slice::align_to_mut, so has the same weak postconditions as that method. You’re only assured that self.len() == prefix.len() + middle.len() * LANES + suffix.len().

Notably, all of the following are possible:

  • prefix.len() >= LANES.
  • middle.is_empty() despite self.len() >= 3 * LANES.
  • suffix.len() >= LANES.

That said, this is a safe method, so if you’re only writing safe code, then this can at most cause incorrect logic, not unsoundness.

This is the mutable version of slice::as_simd; see that for examples.

Panics

This will panic if the size of the SIMD type is different from LANES times that of the scalar.

At the time of writing, the trait restrictions on Simd<T, LANES> keeps that from ever happening, as only power-of-two numbers of lanes are supported. It’s possible that, in the future, those restrictions might be lifted in a way that would make it possible to see panics from this method for something like LANES == 3.

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

Checks if the elements of this slice are sorted.

That is, for each element a and its following element b, a <= b must hold. If the slice yields exactly zero or one element, true is returned.

Note that if Self::Item is only PartialOrd, but not Ord, the above definition implies that this function returns false if any two consecutive items are not comparable.

Examples
#![feature(is_sorted)]
let empty: [i32; 0] = [];

assert!([1, 2, 2, 9].is_sorted());
assert!(![1, 3, 2, 4].is_sorted());
assert!([0].is_sorted());
assert!(empty.is_sorted());
assert!(![0.0, 1.0, f32::NAN].is_sorted());
🔬 This is a nightly-only experimental API. (is_sorted)

Checks if the elements of this slice are sorted using the given comparator function.

Instead of using PartialOrd::partial_cmp, this function uses the given compare function to determine the ordering of two elements. Apart from that, it’s equivalent to is_sorted; see its documentation for more information.

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

Checks if the elements of this slice are sorted using the given key extraction function.

Instead of comparing the slice’s elements directly, this function compares the keys of the elements, as determined by f. Apart from that, it’s equivalent to is_sorted; see its documentation for more information.

Examples
#![feature(is_sorted)]

assert!(["c", "bb", "aaa"].is_sorted_by_key(|s| s.len()));
assert!(![-2i32, -1, 0, 3].is_sorted_by_key(|n| n.abs()));

Returns the index of the partition point according to the given predicate (the index of the first element of the second partition).

The slice is assumed to be partitioned according to the given predicate. This means that all elements for which the predicate returns true are at the start of the slice and all elements for which the predicate returns false are at the end. For example, [7, 15, 3, 5, 4, 12, 6] is a partitioned under the predicate x % 2 != 0 (all odd numbers are at the start, all even at the end).

If this slice is not partitioned, the returned result is unspecified and meaningless, as this method performs a kind of binary search.

See also binary_search, binary_search_by, and binary_search_by_key.

Examples
let v = [1, 2, 3, 3, 5, 6, 7];
let i = v.partition_point(|&x| x < 5);

assert_eq!(i, 4);
assert!(v[..i].iter().all(|&x| x < 5));
assert!(v[i..].iter().all(|&x| !(x < 5)));
🔬 This is a nightly-only experimental API. (slice_take)

Removes the subslice corresponding to the given range and returns a reference to it.

Returns None and does not modify the slice if the given range is out of bounds.

Note that this method only accepts one-sided ranges such as 2.. or ..6, but not 2..6.

Examples

Taking the first three elements of a slice:

#![feature(slice_take)]

let mut slice: &[_] = &['a', 'b', 'c', 'd'];
let mut first_three = slice.take(..3).unwrap();

assert_eq!(slice, &['d']);
assert_eq!(first_three, &['a', 'b', 'c']);

Taking the last two elements of a slice:

#![feature(slice_take)]

let mut slice: &[_] = &['a', 'b', 'c', 'd'];
let mut tail = slice.take(2..).unwrap();

assert_eq!(slice, &['a', 'b']);
assert_eq!(tail, &['c', 'd']);

Getting None when range is out of bounds:

#![feature(slice_take)]

let mut slice: &[_] = &['a', 'b', 'c', 'd'];

assert_eq!(None, slice.take(5..));
assert_eq!(None, slice.take(..5));
assert_eq!(None, slice.take(..=4));
let expected: &[char] = &['a', 'b', 'c', 'd'];
assert_eq!(Some(expected), slice.take(..4));
🔬 This is a nightly-only experimental API. (slice_take)

Removes the subslice corresponding to the given range and returns a mutable reference to it.

Returns None and does not modify the slice if the given range is out of bounds.

Note that this method only accepts one-sided ranges such as 2.. or ..6, but not 2..6.

Examples

Taking the first three elements of a slice:

#![feature(slice_take)]

let mut slice: &mut [_] = &mut ['a', 'b', 'c', 'd'];
let mut first_three = slice.take_mut(..3).unwrap();

assert_eq!(slice, &mut ['d']);
assert_eq!(first_three, &mut ['a', 'b', 'c']);

Taking the last two elements of a slice:

#![feature(slice_take)]

let mut slice: &mut [_] = &mut ['a', 'b', 'c', 'd'];
let mut tail = slice.take_mut(2..).unwrap();

assert_eq!(slice, &mut ['a', 'b']);
assert_eq!(tail, &mut ['c', 'd']);

Getting None when range is out of bounds:

#![feature(slice_take)]

let mut slice: &mut [_] = &mut ['a', 'b', 'c', 'd'];

assert_eq!(None, slice.take_mut(5..));
assert_eq!(None, slice.take_mut(..5));
assert_eq!(None, slice.take_mut(..=4));
let expected: &mut [_] = &mut ['a', 'b', 'c', 'd'];
assert_eq!(Some(expected), slice.take_mut(..4));
🔬 This is a nightly-only experimental API. (slice_take)

Removes the first element of the slice and returns a reference to it.

Returns None if the slice is empty.

Examples
#![feature(slice_take)]

let mut slice: &[_] = &['a', 'b', 'c'];
let first = slice.take_first().unwrap();

assert_eq!(slice, &['b', 'c']);
assert_eq!(first, &'a');
🔬 This is a nightly-only experimental API. (slice_take)

Removes the first element of the slice and returns a mutable reference to it.

Returns None if the slice is empty.

Examples
#![feature(slice_take)]

let mut slice: &mut [_] = &mut ['a', 'b', 'c'];
let first = slice.take_first_mut().unwrap();
*first = 'd';

assert_eq!(slice, &['b', 'c']);
assert_eq!(first, &'d');
🔬 This is a nightly-only experimental API. (slice_take)

Removes the last element of the slice and returns a reference to it.

Returns None if the slice is empty.

Examples
#![feature(slice_take)]

let mut slice: &[_] = &['a', 'b', 'c'];
let last = slice.take_last().unwrap();

assert_eq!(slice, &['a', 'b']);
assert_eq!(last, &'c');
🔬 This is a nightly-only experimental API. (slice_take)

Removes the last element of the slice and returns a mutable reference to it.

Returns None if the slice is empty.

Examples
#![feature(slice_take)]

let mut slice: &mut [_] = &mut ['a', 'b', 'c'];
let last = slice.take_last_mut().unwrap();
*last = 'd';

assert_eq!(slice, &['a', 'b']);
assert_eq!(last, &'d');

Checks if all bytes in this slice are within the ASCII range.

Checks that two slices are an ASCII case-insensitive match.

Same as to_ascii_lowercase(a) == to_ascii_lowercase(b), but without allocating and copying temporaries.

Converts this slice to its ASCII upper case equivalent in-place.

ASCII letters ‘a’ to ‘z’ are mapped to ‘A’ to ‘Z’, but non-ASCII letters are unchanged.

To return a new uppercased value without modifying the existing one, use to_ascii_uppercase.

Converts this slice to its ASCII lower case equivalent in-place.

ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged.

To return a new lowercased value without modifying the existing one, use to_ascii_lowercase.

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

Returns an iterator that produces an escaped version of this slice, treating it as an ASCII string.

Examples
#![feature(inherent_ascii_escape)]

let s = b"0\t\r\n'\"\\\x9d";
let escaped = s.escape_ascii().to_string();
assert_eq!(escaped, "0\\t\\r\\n\\'\\\"\\\\\\x9d");

Sorts the slice.

This sort is stable (i.e., does not reorder equal elements) and O(n * log(n)) worst-case.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See sort_unstable.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples
let mut v = [-5, 4, 1, -3, 2];

v.sort();
assert!(v == [-5, -3, 1, 2, 4]);

Sorts the slice with a comparator function.

This sort is stable (i.e., does not reorder equal elements) and O(n * log(n)) worst-case.

The comparator function must define a total ordering for the elements in the slice. If the ordering is not total, the order of the elements is unspecified. An order is a total order if it is (for all a, b and c):

  • total and antisymmetric: exactly one of a < b, a == b or a > b is true, and
  • transitive, a < b and b < c implies a < c. The same must hold for both == and >.

For example, while f64 doesn’t implement Ord because NaN != NaN, we can use partial_cmp as our sort function when we know the slice doesn’t contain a NaN.

let mut floats = [5f64, 4.0, 1.0, 3.0, 2.0];
floats.sort_by(|a, b| a.partial_cmp(b).unwrap());
assert_eq!(floats, [1.0, 2.0, 3.0, 4.0, 5.0]);

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See sort_unstable_by.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples
let mut v = [5, 4, 1, 3, 2];
v.sort_by(|a, b| a.cmp(b));
assert!(v == [1, 2, 3, 4, 5]);

// reverse sorting
v.sort_by(|a, b| b.cmp(a));
assert!(v == [5, 4, 3, 2, 1]);

Sorts the slice with a key extraction function.

This sort is stable (i.e., does not reorder equal elements) and O(m * n * log(n)) worst-case, where the key function is O(m).

For expensive key functions (e.g. functions that are not simple property accesses or basic operations), sort_by_cached_key is likely to be significantly faster, as it does not recompute element keys.

When applicable, unstable sorting is preferred because it is generally faster than stable sorting and it doesn’t allocate auxiliary memory. See sort_unstable_by_key.

Current implementation

The current algorithm is an adaptive, iterative merge sort inspired by timsort. It is designed to be very fast in cases where the slice is nearly sorted, or consists of two or more sorted sequences concatenated one after another.

Also, it allocates temporary storage half the size of self, but for short slices a non-allocating insertion sort is used instead.

Examples
let mut v = [-5i32, 4, 1, -3, 2];

v.sort_by_key(|k| k.abs());
assert!(v == [1, 2, -3, 4, -5]);

Sorts the slice with a key extraction function.

During sorting, the key function is called at most once per element, by using temporary storage to remember the results of key evaluation. The order of calls to the key function is unspecified and may change in future versions of the standard library.

This sort is stable (i.e., does not reorder equal elements) and O(m * n + n * log(n)) worst-case, where the key function is O(m).

For simple key functions (e.g., functions that are property accesses or basic operations), sort_by_key is likely to be faster.

Current implementation

The current algorithm is based on pattern-defeating quicksort by Orson Peters, which combines the fast average case of randomized quicksort with the fast worst case of heapsort, while achieving linear time on slices with certain patterns. It uses some randomization to avoid degenerate cases, but with a fixed seed to always provide deterministic behavior.

In the worst case, the algorithm allocates temporary storage in a Vec<(K, usize)> the length of the slice.

Examples
let mut v = [-5i32, 4, 32, -3, 2];

v.sort_by_cached_key(|k| k.to_string());
assert!(v == [-3, -5, 2, 32, 4]);

Copies self into a new Vec.

Examples
let s = [10, 40, 30];
let x = s.to_vec();
// Here, `s` and `x` can be modified independently.
🔬 This is a nightly-only experimental API. (allocator_api)

Copies self into a new Vec with an allocator.

Examples
#![feature(allocator_api)]

use std::alloc::System;

let s = [10, 40, 30];
let x = s.to_vec_in(System);
// Here, `s` and `x` can be modified independently.

Creates a vector by repeating a slice n times.

Panics

This function will panic if the capacity would overflow.

Examples

Basic usage:

assert_eq!([1, 2].repeat(3), vec![1, 2, 1, 2, 1, 2]);

A panic upon overflow:

// this will panic at runtime
b"0123456789abcdef".repeat(usize::MAX);

Flattens a slice of T into a single value Self::Output.

Examples
assert_eq!(["hello", "world"].concat(), "helloworld");
assert_eq!([[1, 2], [3, 4]].concat(), [1, 2, 3, 4]);

Flattens a slice of T into a single value Self::Output, placing a given separator between each.

Examples
assert_eq!(["hello", "world"].join(" "), "hello world");
assert_eq!([[1, 2], [3, 4]].join(&0), [1, 2, 0, 3, 4]);
assert_eq!([[1, 2], [3, 4]].join(&[0, 0][..]), [1, 2, 0, 0, 3, 4]);
👎 Deprecated since 1.3.0:

renamed to join

Flattens a slice of T into a single value Self::Output, placing a given separator between each.

Examples
assert_eq!(["hello", "world"].connect(" "), "hello world");
assert_eq!([[1, 2], [3, 4]].connect(&0), [1, 2, 0, 3, 4]);

Returns a vector containing a copy of this slice where each byte is mapped to its ASCII upper case equivalent.

ASCII letters ‘a’ to ‘z’ are mapped to ‘A’ to ‘Z’, but non-ASCII letters are unchanged.

To uppercase the value in-place, use make_ascii_uppercase.

Returns a vector containing a copy of this slice where each byte is mapped to its ASCII lower case equivalent.

ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged.

To lowercase the value in-place, use make_ascii_lowercase.

Trait Implementations

Used for specifying relative comparisons.

The default tolerance to use when testing values that are close together. Read more

A test for equality that uses the absolute difference to compute the approximate equality of two numbers. Read more

The inverse of AbsDiffEq::abs_diff_eq.

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

The resulting type after applying the + operator.

Performs the + operation. Read more

Performs the += operation. Read more

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

The resulting type after applying the & operator.

Performs the & operation. Read more

The resulting type after applying the & operator.

Performs the & operation. Read more

The resulting type after applying the & operator.

Performs the & operation. Read more

The resulting type after applying the & operator.

Performs the & operation. Read more

The resulting type after applying the & operator.

Performs the & operation. Read more

The resulting type after applying the & operator.

Performs the & operation. Read more

Performs the &= operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

The resulting type after applying the | operator.

Performs the | operation. Read more

Performs the |= operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

The resulting type after applying the ^ operator.

Performs the ^ operation. Read more

Performs the ^= operation. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Constrains this value to be between lower and upper (inclusive). Read more

Alias to clamped, which accepts a RangeInclusive parameter instead of two values.

Alias to clamped, which doesn’t take self. Read more

Alias to clamp, which accepts a RangeInclusive parameter instead of two values.

Constrains this value to be between 0 and 1 (inclusive).

Alias to clamped01, which doesn’t take self.

Constrains this value to be between -1 and 1 (inclusive).

Alias to clamped_minus1_1, which doesn’t take self.

Constrains this value to be between lower and upper (inclusive). Read more

Alias to clamped, which accepts a RangeInclusive parameter instead of two values.

Alias to clamped, which doesn’t take self. Read more

Alias to clamp, which accepts a RangeInclusive parameter instead of two values.

Constrains this value to be between 0 and 1 (inclusive).

Alias to clamped01, which doesn’t take self.

Constrains this value to be between -1 and 1 (inclusive).

Alias to clamped_minus1_1, which doesn’t take self.

Returns a copy of the value. Read more

Performs copy-assignment from source. Read more

Formats the value using the given formatter. Read more

Returns the “default value” for a type. Read more

The resulting type after dereferencing.

Dereferences the value.

Mutably dereferences the value.

Deserialize this value from the given Serde deserializer. Read more

Displays the vector, formatted as ({...}, {...}, {...}) where ... are the actual formatting parameters.

Formats the value using the given formatter. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

The resulting type after applying the / operator.

Performs the / operation. Read more

Performs the /= operation. Read more

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

A Vec3 can be created directly from a quaternion’s x, y and z elements.

Performs the conversion.

A Vec3 can be created directly from a quaternion’s x, y and z elements.

Performs the conversion.

Performs the conversion.

A vector can be obtained from a single scalar by broadcasting it.

This conversion is important because it allows scalars to be smoothly accepted as operands in most vector operations.

For instance :

assert_eq!(Vec4::min(4, 5), Vec4::broadcast(4));
assert_eq!(Vec4::max(4, 5), Vec4::broadcast(5));
assert_eq!(Vec4::from(4), Vec4::broadcast(4));
assert_eq!(Vec4::from(4).mul_add(4, 5), Vec4::broadcast(21));

// scaling_3d() logically accepts a Vec3...
let _ = Mat4::<f32>::scaling_3d(Vec3::broadcast(5.0));
// ... but there you go; quick uniform scale, thanks to Into !
let _ = Mat4::scaling_3d(5_f32);

On the other hand, it also allows writing nonsense. To minimize surprises, the names of operations try to be as explicit as possible.

// This creates a matrix that translates to (5,5,5), but it's probably not what you meant.
// Hopefully the `_3d` suffix would help you catch this.
let _ = Mat4::translation_3d(5_f32);
// translation_3d() takes V: Into<Vec3> because it allows it to accept
// Vec2, Vec3 and Vec4, and also with both repr(C) and repr(simd) layouts.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Performs the conversion.

Creates a value from an iterator. Read more

Feeds this value into the given Hasher. Read more

Feeds a slice of this type into the given Hasher. Read more

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

The type of the elements being iterated over.

Which kind of iterator are we turning this into?

Creates an iterator from a value. Read more

bool for scalars, or vector of bools for vectors.

Returns whether this value is between lower and upper (inclusive). Read more

Returns whether this value is between 0 and 1 (inclusive).

Returns whether this value is between the lower and upper bounds of this inclusive range. This is redundant with RangeInclusive::contains(), but is still useful for generics that use the IsBetween trait. Read more

bool for scalars, or vector of bools for vectors.

Returns whether this value is between lower and upper (inclusive). Read more

Returns whether this value is between 0 and 1 (inclusive).

Returns whether this value is between the lower and upper bounds of this inclusive range. This is redundant with RangeInclusive::contains(), but is still useful for generics that use the IsBetween trait. Read more

The resulting type after performing the LERP operation.

Returns the linear interpolation of from to to with factor unconstrained, using a possibly slower but more precise operation. Read more

Returns the linear interpolation of from to to with factor unconstrained, using the supposedly fastest but less precise implementation. Read more

Version of lerp_unclamped() that used a single RangeInclusive parameter instead of two values.

Version of lerp_unclamped_precise() that used a single RangeInclusive parameter instead of two values.

Alias to lerp_unclamped which constrains factor to be between 0 and 1 (inclusive). Read more

Version of lerp() that used a single RangeInclusive parameter instead of two values.

Alias to lerp_unclamped_precise which constrains factor to be between 0 and 1 (inclusive). Read more

Version of lerp_precise() that used a single RangeInclusive parameter instead of two values.

The resulting type after performing the LERP operation.

Returns the linear interpolation of from to to with factor unconstrained, using a possibly slower but more precise operation. Read more

Returns the linear interpolation of from to to with factor unconstrained, using the supposedly fastest but less precise implementation. Read more

Version of lerp_unclamped() that used a single RangeInclusive parameter instead of two values.

Version of lerp_unclamped_precise() that used a single RangeInclusive parameter instead of two values.

Alias to lerp_unclamped which constrains factor to be between 0 and 1 (inclusive). Read more

Version of lerp() that used a single RangeInclusive parameter instead of two values.

Alias to lerp_unclamped_precise which constrains factor to be between 0 and 1 (inclusive). Read more

Version of lerp_precise() that used a single RangeInclusive parameter instead of two values.

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

Multiplies a row vector with a column-major matrix, giving a row vector.

use vek::mat::column_major::Mat4;
use vek::vec::Vec4;

let m = Mat4::new(
    0, 1, 2, 3,
    4, 5, 6, 7,
    8, 9, 0, 1,
    2, 3, 4, 5
);
let v = Vec4::new(0, 1, 2, 3);
let r = Vec4::new(26, 32, 18, 24);
assert_eq!(v * m, r);

The resulting type after applying the * operator.

Performs the * operation. Read more

Multiplies a row vector with a row-major matrix, giving a row vector.

With SIMD vectors, this is the most efficient way.

use vek::mat::row_major::Mat4;
use vek::vec::Vec4;

let m = Mat4::new(
    0, 1, 2, 3,
    4, 5, 6, 7,
    8, 9, 0, 1,
    2, 3, 4, 5
);
let v = Vec4::new(0, 1, 2, 3);
let r = Vec4::new(26, 32, 18, 24);
assert_eq!(v * m, r);

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

Multiplies a column-major matrix with a column vector, giving a column vector.

With SIMD vectors, this is the most efficient way.

use vek::mat::column_major::Mat4;
use vek::vec::Vec4;

let m = Mat4::new(
    0, 1, 2, 3,
    4, 5, 6, 7,
    8, 9, 0, 1,
    2, 3, 4, 5
);
let v = Vec4::new(0, 1, 2, 3);
let r = Vec4::new(14, 38, 12, 26);
assert_eq!(m * v, r);

The resulting type after applying the * operator.

Performs the * operation. Read more

Multiplies a row-major matrix with a column vector, giving a column vector.

use vek::mat::row_major::Mat4;
use vek::vec::Vec4;

let m = Mat4::new(
    0, 1, 2, 3,
    4, 5, 6, 7,
    8, 9, 0, 1,
    2, 3, 4, 5
);
let v = Vec4::new(0, 1, 2, 3);
let r = Vec4::new(14, 38, 12, 26);
assert_eq!(m * v, r);

The resulting type after applying the * operator.

Performs the * operation. Read more

3D vectors can be rotated by being premultiplied by a quaternion, assuming the quaternion is normalized.

The resulting type after applying the * operator.

Performs the * operation. Read more

3D vectors can be rotated by being premultiplied by a quaternion, assuming the quaternion is normalized.

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the * operator.

Performs the * operation. Read more

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

The resulting type after applying the fused multiply-add.

Performs the fused multiply-add operation.

Performs the *= operation. Read more

The resulting type after applying the - operator.

Performs the unary - operation. Read more

The resulting type after applying the ! operator.

Performs the unary ! operation. Read more

Returns the multiplicative identity element of Self, 1. Read more

Sets self to the multiplicative identity element of Self, 1.

Returns true if self is equal to the multiplicative identity. Read more

This method tests for self and other values to be equal, and is used by ==. Read more

This method tests for !=.

Method which takes an iterator and generates Self from the elements by multiplying the items. Read more

The default relative tolerance for testing values that are far-apart. Read more

A test for equality that uses a relative comparison if the values are far apart.

The inverse of RelativeEq::relative_eq.

The resulting type after applying the % operator.

Performs the % operation. Read more

The resulting type after applying the % operator.

Performs the % operation. Read more

The resulting type after applying the % operator.

Performs the % operation. Read more

The resulting type after applying the % operator.

Performs the % operation. Read more

The resulting type after applying the % operator.

Performs the % operation. Read more

The resulting type after applying the % operator.

Performs the % operation. Read more

Performs the %= operation. Read more

Serialize this value into the given Serde serializer. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

The resulting type after applying the << operator.

Performs the << operation. Read more

Performs the <<= operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

The resulting type after applying the >> operator.

Performs the >> operation. Read more

Performs the >>= operation. Read more

The resulting type after performing the SLERP operation.

Performs spherical linear interpolation without implictly constraining factor to be between 0 and 1. Read more

Performs spherical linear interpolation, constraining factor to be between 0 and 1. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

The resulting type after applying the - operator.

Performs the - operation. Read more

Performs the -= operation. Read more

Method which takes an iterator and generates Self from the elements by “summing up” the items. Read more

The default ULPs to tolerate when testing values that are far-apart. Read more

A test for equality that uses units in the last place (ULP) if the values are far apart.

The inverse of UlpsEq::ulps_eq.

Returns this value, wrapped between zero and some upper bound (both inclusive). Read more

Returns this value, wrapped between lower (inclusive) and upper (exclusive). Read more

Wraps a value such that it goes back and forth from zero to upper (inclusive) as it increases. Read more

Alias to wrapped() which doesn’t take self. Read more

Returns this value, wrapped between zero and two times 𝛑 (inclusive). Read more

Alias to wrapped_2pi which doesn’t take self. Read more

Alias to wrapped_between which doesn’t take self. Read more

Calculates the shortest difference between two given angles, in radians.

Calculates the shortest difference between two given angles, in degrees. Read more

Returns this value, wrapped between zero and some upper bound (both inclusive). Read more

Returns this value, wrapped between lower (inclusive) and upper (exclusive). Read more

Wraps a value such that it goes back and forth from zero to upper (inclusive) as it increases. Read more

Alias to wrapped() which doesn’t take self. Read more

Returns this value, wrapped between zero and two times 𝛑 (inclusive). Read more

Alias to wrapped_2pi which doesn’t take self. Read more

Alias to wrapped_between which doesn’t take self. Read more

Calculates the shortest difference between two given angles, in radians.

Calculates the shortest difference between two given angles, in degrees. Read more

Returns the additive identity element of Self, 0. Read more

Returns true if self is equal to the additive identity.

Sets self to the additive identity element of Self, 0.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Performs the conversion.

Performs the conversion.

The resulting type after obtaining ownership.

Creates owned data from borrowed data, usually by cloning. Read more

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

Uses borrowed data to replace owned data, usually by cloning. Read more

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.