Struct Val

#[repr(C)]
pub struct Val { /* private fields */ }

Val is a wrapper around emscripten’s EM_VAL type, which itself represents javascript objects

Implementations

impl Val

pub fn global(name: &str) -> Self

Looks up a global value represented by name

pub fn take_ownership(v: EM_VAL) -> Self

Creates a Val from a raw handle. This can be used for retrieving values from JavaScript, where the JavaScript side should wrap a value with Emval.toHandle, pass it to Rust, and then Rust can use take_ownership to convert it to a Val instance

pub fn from_val(v: &Val) -> Self

Create a Val from another Val instance

pub fn undefined() -> Self

Create a Val that represents undefined

pub fn object() -> Self

Creates a new Object

pub fn null() -> Self

Create a Val that represents null

pub fn array() -> Self

Creates and returns a new Array

pub fn from_str(s: &str) -> Self

Creates a Val from a string slice

pub fn module_property(s: &str) -> Self

Looks up a value by the provided name on the Emscripten Module object.

pub fn from_array<T: Clone + Into<Val>>(arr: &[T]) -> Self

Creates a Val from an array

pub fn as_handle(&self) -> EM_VAL

Get the EM_VAL handle of a Val object

pub fn call(&self, f: &str, args: &[&Val]) -> Val

Call a method associated with the JS object represented by the Val object

pub fn get<T: Clone + Into<Val>>(&self, prop: &T) -> Val

Get a property

pub fn set<T: Clone + Into<Val>, U: Clone + Into<Val>>(&self, prop: &T, val: &U)

Set a property

pub fn from_i32(i: i32) -> Self

Generate a Val object from an i32

pub fn from_u32(i: u32) -> Self

Generate a Val object from an u32

pub fn from_f32(i: f32) -> Self

Generate a Val object from an f32

pub fn from_f64(i: f64) -> Self

Generate a Val object from an f64

pub fn from_bool(i: bool) -> Self

Generate a Val object from a bool

pub fn release_ownership(&mut self) -> EM_VAL

Get and release ownership of the internal handle

pub fn has_own_property(&self, key: &str) -> bool

Checks if the JavaScript object has own (non-inherited) property with the specified name.

pub fn as_f64(&self) -> f64

Converts current value to an f64

pub fn as_f32(&self) -> f32

Converts current value to an f32

pub fn as_i32(&self) -> i32

Converts current value to an i32

pub fn as_u32(&self) -> u32

Converts current value to a u32

pub fn as_bool(&self) -> bool

Converts current value to a bool. This can be useful also to check if a returned object is valid

pub fn as_string(&self) -> String

Converts current value to a string

pub fn is_null(&self) -> bool

Checks whether a value is null

pub fn is_undefined(&self) -> bool

Checks whether a value is undefined

pub fn is_true(&self) -> bool

Checks whether a value is true

pub fn is_false(&self) -> bool

Checks whether a value is false

pub fn is_number(&self) -> bool

Checks whether a value is a number

pub fn is_string(&self) -> bool

Checks whether a value is a string

pub fn instanceof(&self, v: &Val) -> bool

Checks whether the object is an instanceof another object

pub fn is_array(&self) -> bool

Checks whether a value is an Array

pub fn is_in(&self, v: &Val) -> bool

Checks if the specified property is in the specified object

pub fn type_of(&self) -> Val

Returns the typeof the object

pub fn throw(&self) -> bool

Throw the object as a JS exception

pub fn await_(&self) -> Val

Pauses the Rust code to await the Promise / thenable. This requires ASYNCIFY to be enabled

pub fn delete<T: Clone + Into<Val>>(&self, prop: &T) -> bool

Removes a property from an object

pub fn new(&self, args: &[&Val]) -> Val

Instantiate a new object, passes the args to the object’s contructor

pub fn strictly_equals<T: Clone + Into<Val>>(&self, v: &T) -> bool

Check if the current object is strictly equals to another object ===

pub fn not(&self) -> bool

Checks the validity of an object

pub fn add_event_listener<F: FnMut(&Val) -> Val + 'static>( &self, ev: &str, f: F, )

Convenience method. Adds a callback to an EventTarget object

pub fn from_fn0<F: FnMut() -> Val + 'static>(f: F) -> Val

Generates a Val object from a function object which takes 0 args

pub fn from_fn1<F: FnMut(&Val) -> Val + 'static>(f: F) -> Val

Generates a Val object from a function object which takes 1 arg

pub fn from_fn2<F: FnMut(&Val, &Val) -> Val + 'static>(f: F) -> Val

Generates a Val object from a function object which takes 2 args

pub fn from_fn3<F: FnMut(&Val, &Val, &Val) -> Val + 'static>(f: F) -> Val

Generates a Val object from a function object which takes 3 args

pub fn from_fn4<F: FnMut(&Val, &Val, &Val, &Val) -> Val + 'static>(f: F) -> Val

Generates a Val object from a function object which takes 4 args

pub fn to_vec<T: Clone + From<Val>>(&self) -> Vec<T>

Convert a javascript Array to a Rust Vec

Trait Implementations

impl Clone for Val

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Default for Val

fn default() -> Val

Returns the “default value” for a type.

impl Drop for Val

fn drop(&mut self)

Executes the destructor for this type.

impl From<&Val> for Val

fn from(item: &Val) -> Self

Converts to this type from the input type.

impl From<&str> for Val

fn from(item: &str) -> Self

Converts to this type from the input type.

impl From<()> for Val

fn from(_: ()) -> Self

Converts to this type from the input type.

impl From<Val> for String

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<Val> for bool

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<Val> for f32

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<Val> for f64

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<Val> for i32

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<Val> for u32

fn from(item: Val) -> Self

Converts to this type from the input type.

impl From<bool> for Val

fn from(item: bool) -> Self

Converts to this type from the input type.

impl From<f32> for Val

fn from(item: f32) -> Self

Converts to this type from the input type.

impl From<f64> for Val

fn from(item: f64) -> Self

Converts to this type from the input type.

impl From<i32> for Val

fn from(item: i32) -> Self

Converts to this type from the input type.

impl From<u32> for Val

fn from(item: u32) -> Self

Converts to this type from the input type.

impl PartialEq for Val

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Val

fn partial_cmp(&self, other: &Val) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for Val