Enum Value

pub enum Value {
    Undefined,
    Null,
    Boolean(bool),
    Number(f64),
    Date(f64),
    String(String),
    Array(Array),
    Function(Function),
    Object(Object),
}

A JavaScript value.

Values can either hold direct values (undefined, null, booleans, numbers, dates) or references (strings, arrays, functions, other objects). Cloning values (via Rust’s Clone) of the direct types defers to Rust’s Copy, while cloning values of the referential types results in a simple reference clone similar to JavaScript’s own “by-reference” semantics.

Variants

Undefined

The JavaScript value undefined.

Null

The JavaScript value null.

Boolean(bool)

The JavaScript value true or false.

Number(f64)

A JavaScript floating point number.

Date(f64)

Elapsed milliseconds since Unix epoch.

String(String)

An immutable JavaScript string, managed by V8.

Array(Array)

Reference to a JavaScript arrray.

Function(Function)

Reference to a JavaScript function.

Object(Object)

Reference to a JavaScript object. If a value is a function or an array in JavaScript, it will be converted to Value::Array or Value::Function instead of Value::Object.

Implementations

impl Value

pub fn is_undefined(&self) -> bool

Returns true if this is a Value::Undefined, false otherwise.

pub fn is_null(&self) -> bool

Returns true if this is a Value::Null, false otherwise.

pub fn is_boolean(&self) -> bool

Returns true if this is a Value::Boolean, false otherwise.

pub fn is_number(&self) -> bool

Returns true if this is a Value::Number, false otherwise.

pub fn is_date(&self) -> bool

Returns true if this is a Value::Date, false otherwise.

pub fn is_string(&self) -> bool

Returns true if this is a Value::String, false otherwise.

pub fn is_array(&self) -> bool

Returns true if this is a Value::Array, false otherwise.

pub fn is_function(&self) -> bool

Returns true if this is a Value::Function, false otherwise.

pub fn is_object(&self) -> bool

Returns true if this is a Value::Object, false otherwise.

pub fn as_undefined(&self) -> Option<()>

Returns Some(()) if this is a Value::Undefined, None otherwise.

pub fn as_null(&self) -> Option<()>

Returns Some(()) if this is a Value::Null, None otherwise.

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

Returns Some if this is a Value::Boolean, None otherwise.

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

Returns Some if this is a Value::Number, None otherwise.

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

Returns Some if this is a Value::Date, None otherwise.

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

Returns Some if this is a Value::String, None otherwise.

pub fn as_array(&self) -> Option<&Array>

Returns Some if this is a Value::Array, None otherwise.

pub fn as_function(&self) -> Option<&Function>

Returns Some if this is a Value::Function, None otherwise.

pub fn as_object(&self) -> Option<&Object>

Returns Some if this is a Value::Object, None otherwise.

pub fn into<T: FromValue>(self, mv8: &MiniV8) -> Result<T>

A wrapper around FromValue::from_value.

pub fn coerce_boolean(&self, mv8: &MiniV8) -> bool

Coerces a value to a boolean. Returns true if the value is “truthy”, false otherwise.

pub fn coerce_number(&self, mv8: &MiniV8) -> Result<f64>

Coerces a value to a number. Nearly all JavaScript values are coercible to numbers, but this may fail with a runtime error under extraordinary circumstances (e.g. if the ECMAScript ToNumber implementation throws an error).

This will return std::f64::NAN if the value has no numerical equivalent.

pub fn coerce_string(&self, mv8: &MiniV8) -> Result<String>

Coerces a value to a string. Nearly all JavaScript values are coercible to strings, but this may fail with a runtime error if toString() fails or under otherwise extraordinary circumstances (e.g. if the ECMAScript ToString implementation throws an error).

Trait Implementations

impl Clone for Value

fn clone(&self) -> Value

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Value

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

Formats the value using the given formatter.

impl FromIterator<Value> for Values

fn from_iter<I: IntoIterator<Item = Value>>(iter: I) -> Self

Creates a value from an iterator.

impl FromValue for Value

fn from_value(value: Value, _mv8: &MiniV8) -> Result<Self>

Performs the conversion.

impl ToValue for Value

fn to_value(self, _mv8: &MiniV8) -> Result<Value>

Performs the conversion.