Struct js_sys::Symbol

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#[repr(transparent)]pub struct Symbol { /* fields omitted */ }

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Implementations

impl Symbol[−]

pub fn has_instance() -> Symbol[−]

The Symbol.hasInstance well-known symbol is used to determine if a constructor object recognizes an object as its instance. The instanceof operator's behavior can be customized by this symbol.

MDN documentation

impl Symbol[−]

pub fn is_concat_spreadable() -> Symbol[−]

The Symbol.isConcatSpreadable well-known symbol is used to configure if an object should be flattened to its array elements when using the Array.prototype.concat() method.

MDN documentation

impl Symbol[−]

pub fn async_iterator() -> Symbol[−]

The Symbol.asyncIterator well-known symbol specifies the default AsyncIterator for an object. If this property is set on an object, it is an async iterable and can be used in a for await...of loop.

MDN documentation

impl Symbol[−]

pub fn iterator() -> Symbol[−]

The Symbol.iterator well-known symbol specifies the default iterator for an object. Used by for...of.

MDN documentation

impl Symbol[−]

pub fn match_() -> Symbol[−]

The Symbol.match well-known symbol specifies the matching of a regular expression against a string. This function is called by the String.prototype.match() method.

MDN documentation

impl Symbol[−]

pub fn replace() -> Symbol[−]

The Symbol.replace well-known symbol specifies the method that replaces matched substrings of a string. This function is called by the String.prototype.replace() method.

For more information, see RegExp.prototype[@@replace]() and String.prototype.replace().

MDN documentation

impl Symbol[−]

pub fn search() -> Symbol[−]

The Symbol.search well-known symbol specifies the method that returns the index within a string that matches the regular expression. This function is called by the String.prototype.search() method.

For more information, see RegExp.prototype[@@search]() and String.prototype.search().

MDN documentation

impl Symbol[−]

pub fn species() -> Symbol[−]

The well-known symbol Symbol.species specifies a function-valued property that the constructor function uses to create derived objects.

MDN documentation

impl Symbol[−]

pub fn split() -> Symbol[−]

The Symbol.split well-known symbol specifies the method that splits a string at the indices that match a regular expression. This function is called by the String.prototype.split() method.

For more information, see RegExp.prototype[@@split]() and String.prototype.split(). MDN documentation

impl Symbol[−]

pub fn to_primitive() -> Symbol[−]

The Symbol.toPrimitive is a symbol that specifies a function valued property that is called to convert an object to a corresponding primitive value.

MDN documentation

impl Symbol[−]

pub fn to_string_tag() -> Symbol[−]

The Symbol.toStringTag well-known symbol is a string valued property that is used in the creation of the default string description of an object. It is accessed internally by the Object.prototype.toString() method.

MDN documentation

impl Symbol[−]

pub fn for_(key: &str) -> Symbol[−]

The Symbol.for(key) method searches for existing symbols in a runtime-wide symbol registry with the given key and returns it if found. Otherwise a new symbol gets created in the global symbol registry with this key.

MDN documentation

impl Symbol[−]

pub fn key_for(sym: &Symbol) -> JsValue[−]

The Symbol.keyFor(sym) method retrieves a shared symbol key from the global symbol registry for the given symbol.

MDN documentation

impl Symbol[−]

pub fn to_string(&self) -> JsString[−]

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

MDN documentation

impl Symbol[−]

pub fn unscopables() -> Symbol[−]

The Symbol.unscopables well-known symbol is used to specify an object value of whose own and inherited property names are excluded from the with environment bindings of the associated object.

MDN documentation

impl Symbol[−]

pub fn value_of(&self) -> Symbol[−]

The valueOf() method returns the primitive value of a Symbol 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<JsValue> for Symbol[+]

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fn as_ref(&self) -> &JsValue[−]

Performs the conversion.

impl AsRef<Symbol> for Symbol[+]

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fn as_ref(&self) -> &Symbol[−]

Performs the conversion.

impl Clone for Symbol[+]

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fn clone(&self) -> Symbol[−]

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)[−]

Performs copy-assignment from source.

impl Debug for Symbol[+]

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

Formats the value using the given formatter.

impl Deref for Symbol[+]

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type Target = JsValue

The resulting type after dereferencing.

fn deref(&self) -> &JsValue[−]

Dereferences the value.

impl From<JsValue> for Symbol[+]

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fn from(obj: JsValue) -> Symbol[−]

Performs the conversion.

impl From<Symbol> for JsValue[+]

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fn from(obj: Symbol) -> JsValue[−]

Performs the conversion.

impl FromWasmAbi for Symbol[+]

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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 Symbol[+]

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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 Symbol[+]

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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 Symbol[+]

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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 Symbol[+]

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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 Symbol[+]

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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 Symbol[+]

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fn none() -> Self::Abi[−]

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

impl RefFromWasmAbi for Symbol[+]

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type Abi = <JsValue as RefFromWasmAbi>::Abi

The wasm ABI type references to Self are recovered from.

type Anchor = ManuallyDrop<Symbol>

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 Symbol[+]

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fn describe()