Struct js_sys::Array

#[repr(transparent)]
pub struct Array { /* private fields */ }

Implementations

impl Array

pub fn new() -> Array

Creates a new empty array.

impl Array

pub fn new_with_length(len: u32) -> Array

Creates a new array with the specified length (elements are initialized to undefined).

impl Array

pub fn get(&self, index: u32) -> JsValue

Retrieves the element at the index (returns undefined if the index is out of range).

impl Array

pub fn set(&self, index: u32, value: JsValue)

Sets the element at the index (auto-enlarges the array if the index is out of range).

impl Array

pub fn delete(&self, index: u32)

Deletes the element at the index (does nothing if the index is out of range).

The element at the index is set to undefined.

This does not resize the array, the array will still be the same length.

impl Array

pub fn from(val: &JsValue) -> Array

The Array.from() method creates a new, shallow-copied Array instance from an array-like or iterable object.

impl Array

pub fn copy_within(&self, target: i32, start: i32, end: i32) -> Array

The copyWithin() method shallow copies part of an array to another location in the same array and returns it, without modifying its size.

MDN documentation

impl Array

pub fn concat(&self, array: &Array) -> Array

The concat() method is used to merge two or more arrays. This method does not change the existing arrays, but instead returns a new array.

MDN documentation

impl Array

pub fn every(
    &self,
    predicate: &mut dyn FnMut(JsValue, u32, Array) -> bool
) -> bool

The every() method tests whether all elements in the array pass the test implemented by the provided function.

MDN documentation

impl Array

pub fn fill(&self, value: &JsValue, start: u32, end: u32) -> Array

The fill() method fills all the elements of an array from a start index to an end index with a static value. The end index is not included.

MDN documentation

impl Array

pub fn filter(
    &self,
    predicate: &mut dyn FnMut(JsValue, u32, Array) -> bool
) -> Array

The filter() method creates a new array with all elements that pass the test implemented by the provided function.

MDN documentation

impl Array

pub fn find(
    &self,
    predicate: &mut dyn FnMut(JsValue, u32, Array) -> bool
) -> JsValue

The find() method returns the value of the first element in the array that satisfies the provided testing function. Otherwise undefined is returned.

MDN documentation

impl Array

pub fn find_index(
    &self,
    predicate: &mut dyn FnMut(JsValue, u32, Array) -> bool
) -> i32

The findIndex() method returns the index of the first element in the array that satisfies the provided testing function. Otherwise -1 is returned.

MDN documentation

impl Array

pub fn flat(&self, depth: i32) -> Array

The flat() method creates a new array with all sub-array elements concatenated into it recursively up to the specified depth.

MDN documentation

impl Array

pub fn flat_map(
    &self,
    callback: &mut dyn FnMut(JsValue, u32, Array) -> Vec<JsValue>
) -> Array

The flatMap() method first maps each element using a mapping function, then flattens the result into a new array.

MDN documentation

impl Array

pub fn for_each(&self, callback: &mut dyn FnMut(JsValue, u32, Array))

The forEach() method executes a provided function once for each array element.

MDN documentation

impl Array

pub fn includes(&self, value: &JsValue, from_index: i32) -> bool

The includes() method determines whether an array includes a certain element, returning true or false as appropriate.

MDN documentation

impl Array

pub fn index_of(&self, value: &JsValue, from_index: i32) -> i32

The indexOf() method returns the first index at which a given element can be found in the array, or -1 if it is not present.

MDN documentation

impl Array

pub fn is_array(value: &JsValue) -> bool

The Array.isArray() method determines whether the passed value is an Array.

MDN documentation

impl Array

pub fn join(&self, delimiter: &str) -> JsString

The join() method joins all elements of an array (or an array-like object) into a string and returns this string.

MDN documentation

impl Array

pub fn last_index_of(&self, value: &JsValue, from_index: i32) -> i32

The lastIndexOf() method returns the last index at which a given element can be found in the array, or -1 if it is not present. The array is searched backwards, starting at fromIndex.

MDN documentation

impl Array

pub fn length(&self) -> u32

The length property of an object which is an instance of type Array sets or returns the number of elements in that array. The value is an unsigned, 32-bit integer that is always numerically greater than the highest index in the array.

MDN documentation

impl Array

pub fn map(
    &self,
    predicate: &mut dyn FnMut(JsValue, u32, Array) -> JsValue
) -> Array

map() calls a provided callback function once for each element in an array, in order, and constructs a new array from the results. callback is invoked only for indexes of the array which have assigned values, including undefined. It is not called for missing elements of the array (that is, indexes that have never been set, which have been deleted or which have never been assigned a value).

MDN documentation

impl Array

pub fn of1(a: &JsValue) -> Array

The Array.of() method creates a new Array instance with a variable number of arguments, regardless of number or type of the arguments.

The difference between Array.of() and the Array constructor is in the handling of integer arguments: Array.of(7) creates an array with a single element, 7, whereas Array(7) creates an empty array with a length property of 7 (Note: this implies an array of 7 empty slots, not slots with actual undefined values).

MDN documentation

Notes

There are a few bindings to of in js-sys: of1, of2, etc… with different arities.

impl Array

pub fn of2(a: &JsValue, b: &JsValue) -> Array

MDN documentation

impl Array

pub fn of3(a: &JsValue, b: &JsValue, c: &JsValue) -> Array

MDN documentation

impl Array

pub fn of4(a: &JsValue, b: &JsValue, c: &JsValue, d: &JsValue) -> Array

MDN documentation

impl Array

pub fn of5(
    a: &JsValue,
    b: &JsValue,
    c: &JsValue,
    d: &JsValue,
    e: &JsValue
) -> Array

MDN documentation

impl Array

pub fn pop(&self) -> JsValue

The pop() method removes the last element from an array and returns that element. This method changes the length of the array.

MDN documentation

impl Array

pub fn push(&self, value: &JsValue) -> u32

The push() method adds one or more elements to the end of an array and returns the new length of the array.

MDN documentation

impl Array

pub fn reduce(
    &self,
    predicate: &mut dyn FnMut(JsValue, JsValue, u32, Array) -> JsValue,
    initial_value: &JsValue
) -> JsValue

The reduce() method applies a function against an accumulator and each element in the array (from left to right) to reduce it to a single value.

MDN documentation

impl Array

pub fn reduce_right(
    &self,
    predicate: &mut dyn FnMut(JsValue, JsValue, u32, Array) -> JsValue,
    initial_value: &JsValue
) -> JsValue

The reduceRight() method applies a function against an accumulator and each value of the array (from right-to-left) to reduce it to a single value.

MDN documentation

impl Array

pub fn reverse(&self) -> Array

The reverse() method reverses an array in place. The first array element becomes the last, and the last array element becomes the first.

MDN documentation

impl Array

pub fn shift(&self) -> JsValue

The shift() method removes the first element from an array and returns that removed element. This method changes the length of the array.

MDN documentation

impl Array

pub fn slice(&self, start: u32, end: u32) -> Array

The slice() method returns a shallow copy of a portion of an array into a new array object selected from begin to end (end not included). The original array will not be modified.

MDN documentation

impl Array

pub fn some(&self, predicate: &mut dyn FnMut(JsValue) -> bool) -> bool

The some() method tests whether at least one element in the array passes the test implemented by the provided function. Note: This method returns false for any condition put on an empty array. MDN documentation

impl Array

pub fn sort(&self) -> Array

The sort() method sorts the elements of an array in place and returns the array. The sort is not necessarily stable. The default sort order is according to string Unicode code points.

The time and space complexity of the sort cannot be guaranteed as it is implementation dependent.

MDN documentation

impl Array

pub fn splice(&self, start: u32, delete_count: u32, item: &JsValue) -> Array

The splice() method changes the contents of an array by removing existing elements and/or adding new elements.

MDN documentation

impl Array

pub fn to_locale_string(&self, locales: &JsValue, options: &JsValue) -> JsString

The toLocaleString() method returns a string representing the elements of the array. The elements are converted to Strings using their toLocaleString methods and these Strings are separated by a locale-specific String (such as a comma “,”).

MDN documentation

impl Array

pub fn to_string(&self) -> JsString

The toString() method returns a string representing the specified array and its elements.

MDN documentation

impl Array

pub fn unshift(&self, value: &JsValue) -> u32

The unshift() method adds one or more elements to the beginning of an array and returns the new length of the array.

MDN documentation

impl Array

pub fn iter(&self) -> ArrayIter<'_>

Returns an iterator over the values of the JS array.

pub fn to_vec(&self) -> Vec<JsValue>

Converts the JS array into a new Vec.

impl Array

pub fn keys(&self) -> Iterator

The keys() method returns a new Array Iterator object that contains the keys for each index in the array.

MDN documentation

impl Array

pub fn entries(&self) -> Iterator

The entries() method returns a new Array Iterator object that contains the key/value pairs for each index in the array.

MDN documentation

impl Array

pub fn values(&self) -> Iterator

The values() method returns a new Array Iterator object that contains the values for each index in the array.

MDN documentation

Methods from Deref<Target = Object>

pub fn constructor(&self) -> Function

The constructor property returns a reference to the Object constructor function that created the instance object.

MDN documentation

pub fn has_own_property(&self, property: &JsValue) -> bool

The hasOwnProperty() method returns a boolean indicating whether the object has the specified property as its own property (as opposed to inheriting it).

MDN documentation

pub fn is_prototype_of(&self, value: &JsValue) -> bool

The isPrototypeOf() method checks if an object exists in another object’s prototype chain.

MDN documentation

pub fn property_is_enumerable(&self, property: &JsValue) -> bool

The propertyIsEnumerable() method returns a Boolean indicating whether the specified property is enumerable.

MDN documentation

pub fn to_locale_string(&self) -> JsString

The toLocaleString() method returns a string representing the object. This method is meant to be overridden by derived objects for locale-specific purposes.

MDN documentation

pub fn to_string(&self) -> JsString

The toString() method returns a string representing the object.

MDN documentation

pub fn value_of(&self) -> Object

The valueOf() method returns the primitive value of the specified object.

MDN documentation

Methods from Deref<Target = JsValue>

pub const NULL: JsValue

pub const UNDEFINED: JsValue

pub const TRUE: JsValue

pub const FALSE: JsValue

pub fn as_f64(&self) -> Option<f64>

Returns the f64 value of this JS value if it’s an instance of a number.

If this JS value is not an instance of a number then this returns None.

pub fn is_string(&self) -> bool

Tests whether this JS value is a JS string.

pub fn as_string(&self) -> Option<String>

If this JS value is a string value, this function copies the JS string value into wasm linear memory, encoded as UTF-8, and returns it as a Rust String.

To avoid the copying and re-encoding, consider the JsString::try_from() function from js-sys instead.

If this JS value is not an instance of a string or if it’s not valid utf-8 then this returns None.

UTF-16 vs UTF-8

JavaScript strings in general are encoded as UTF-16, but Rust strings are encoded as UTF-8. This can cause the Rust string to look a bit different than the JS string sometimes. For more details see the documentation about the str type which contains a few caveats about the encodings.

pub fn as_bool(&self) -> Option<bool>

Returns the bool value of this JS value if it’s an instance of a boolean.

If this JS value is not an instance of a boolean then this returns None.

pub fn is_null(&self) -> bool

Tests whether this JS value is null

pub fn is_undefined(&self) -> bool

Tests whether this JS value is undefined

pub fn is_symbol(&self) -> bool

Tests whether the type of this JS value is symbol

pub fn is_object(&self) -> bool

Tests whether typeof self == "object" && self !== null.

pub fn is_function(&self) -> bool

Tests whether the type of this JS value is function.

pub fn is_truthy(&self) -> bool

Tests whether the value is “truthy”.

pub fn is_falsy(&self) -> bool

Tests whether the value is “falsy”.

Trait Implementations

impl AsRef<Array> for Array

fn as_ref(&self) -> &Array

Performs the conversion.

impl AsRef<JsValue> for Array

fn as_ref(&self) -> &JsValue

Performs the conversion.

impl AsRef<Object> for Array

fn as_ref(&self) -> &Object

Performs the conversion.

impl Clone for Array

fn clone(&self) -> Array

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Array

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Array

fn default() -> Self

Returns the “default value” for a type.

impl Deref for Array

type Target = Object

The resulting type after dereferencing.

fn deref(&self) -> &Object

Dereferences the value.

impl From<Array> for JsValue

fn from(obj: Array) -> JsValue

Performs the conversion.

impl From<Array> for Object

fn from(obj: Array) -> Object

Performs the conversion.

impl From<JsValue> for Array

fn from(obj: JsValue) -> Array

Performs the conversion.

impl<A> FromIterator<A> for Array where
    A: AsRef<JsValue>, 

fn from_iter<T>(iter: T) -> Array where
    T: IntoIterator<Item = A>, 

Creates a value from an iterator.

impl FromWasmAbi for Array

type Abi = <JsValue as FromWasmAbi>::Abi

The wasm ABI type that this converts from when coming back out from the ABI boundary.

unsafe fn from_abi(js: Self::Abi) -> Self

Recover a Self from Self::Abi.

impl IntoWasmAbi for Array

type Abi = <JsValue as IntoWasmAbi>::Abi

The wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl<'a> IntoWasmAbi for &'a Array

type Abi = <&'a JsValue as IntoWasmAbi>::Abi

The wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl JsCast for Array

fn instanceof(val: &JsValue) -> bool

Performs a dynamic instanceof check to see whether the JsValue provided is an instance of this type.

fn is_type_of(val: &JsValue) -> bool

Performs a dynamic check to see whether the JsValue provided is a value of this type.

fn unchecked_from_js(val: JsValue) -> Self

Performs a zero-cost unchecked conversion from a JsValue into an instance of Self

fn unchecked_from_js_ref(val: &JsValue) -> &Self

Performs a zero-cost unchecked conversion from a &JsValue into an instance of &Self.

fn has_type<T>(&self) -> bool where
    T: JsCast, 

Test whether this JS value has a type T.

fn dyn_into<T>(self) -> Result<T, Self> where
    T: JsCast, 

Performs a dynamic cast (checked at runtime) of this value into the target type T.

fn dyn_ref<T>(&self) -> Option<&T> where
    T: JsCast, 

Performs a dynamic cast (checked at runtime) of this value into the target type T.

fn unchecked_into<T>(self) -> T where
    T: JsCast, 

Performs a zero-cost unchecked cast into the specified type.

fn unchecked_ref<T>(&self) -> &T where
    T: JsCast, 

Performs a zero-cost unchecked cast into a reference to the specified type.

fn is_instance_of<T>(&self) -> bool where
    T: JsCast, 

Test whether this JS value is an instance of the type T.

impl OptionFromWasmAbi for Array

fn is_none(abi: &Self::Abi) -> bool

Tests whether the argument is a “none” instance. If so it will be deserialized as None, and otherwise it will be passed to FromWasmAbi.

impl OptionIntoWasmAbi for Array

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option.

impl<'a> OptionIntoWasmAbi for &'a Array

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option.

impl PartialEq<Array> for Array

fn eq(&self, other: &Array) -> bool

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

fn ne(&self, other: &Array) -> bool

This method tests for !=.

impl RefFromWasmAbi for Array

type Abi = <JsValue as RefFromWasmAbi>::Abi

The wasm ABI type references to Self are recovered from.

type Anchor = ManuallyDrop<Array>

The type that holds the reference to Self for the duration of the invocation of the function that has an &Self parameter. This is required to ensure that the lifetimes don’t persist beyond one function call, and so that they remain anonymous.

unsafe fn ref_from_abi(js: Self::Abi) -> Self::Anchor

Recover a Self::Anchor from Self::Abi.

impl WasmDescribe for Array

fn describe()

impl Eq for Array

impl StructuralEq for Array

impl StructuralPartialEq for Array