Struct JsHost 

pub struct JsHost {
    pub funcs: Vec<FuncDef>,
    pub tries: Vec<TryDef>,
    pub error: Option<String>,
    pub exc: Option<Value>,
    pub signal: Option<Signal>,
    /* private fields */
}

The JavaScript runtime.

Fields

funcs: Vec<FuncDef>

Function templates, indexed by def id.

tries: Vec<TryDef>

try/catch/finally block templates, indexed by try id.

error: Option<String>

exc: Option<Value>

The in-flight thrown value, if any (JS throw).

signal: Option<Signal>

Implementations

impl JsHost

pub fn new() -> JsHost

pub fn null(&self) -> Value

pub fn is_null(&self, v: &Value) -> bool

pub fn program_offsets(&self) -> (usize, usize)

pub fn load_program(&mut self, funcs: Vec<FuncDef>, tries: Vec<TryDef>)

pub fn try_def(&self, id: usize) -> Option<TryDef>

pub fn alloc(&mut self, obj: JsObj) -> Value

pub fn get(&self, v: &Value) -> Option<&JsObj>

pub fn get_mut(&mut self, v: &Value) -> Option<&mut JsObj>

pub fn new_str(&mut self, s: impl Into<String>) -> Value

pub fn new_array(&mut self, items: Vec<Value>) -> Value

pub fn new_object(&mut self, props: IndexMap<String, Value>) -> Value

pub fn as_str(&self, v: &Value) -> Option<String>

pub fn read_name(&self, name: &str) -> Option<Value>

Scope-chain read: local + enclosing chain, then globals.

pub fn read_global(&self, name: &str) -> Option<Value>

pub fn set_name(&mut self, name: &str, val: Value)

Assign to an existing binding up the scope chain, else create a global (JS assignment to an undeclared name targets the global object).

pub fn declare_name(&mut self, name: &str, val: Value)

Declare a new binding in the current scope (let/const/var).

pub fn set_global(&mut self, name: &str, val: Value)

pub fn del_name(&mut self, name: &str)

pub fn current_this(&self) -> Option<Value>

pub fn current_env_capture(&self) -> Env

pub fn take_error(&mut self) -> Option<String>

pub fn raise_str(&mut self, class: &str, msg: &str) -> String

impl JsHost

pub fn type_of(&self, v: &Value) -> &'static str

The typeof string for v.

pub fn truthy(&self, v: &Value) -> bool

JS truthiness: false / 0 / -0 / NaN / “” / null / undefined are falsy.

pub fn to_number(&self, v: &Value) -> f64

Coerce to a number (ToNumber): the arithmetic-context conversion.

pub fn str_of(&self, v: &Value) -> String

String(v) — the string-coercion form (raw, unquoted).

pub fn console_format(&self, v: &Value) -> String

console.log-style rendering of a top-level argument: bare strings print raw; everything else uses inspect.

pub fn inspect(&self, v: &Value) -> String

util.inspect-style rendering (nested; strings quoted).

pub fn strict_eq(&self, a: &Value, b: &Value) -> bool

Strict equality (===): same type and same value, no coercion.

pub fn is_nullish(&self, v: &Value) -> bool

Whether v is null or undefined.

pub fn loose_eq(&self, a: &Value, b: &Value) -> bool

Loose equality (==) following the ECMAScript Abstract Equality Comparison. Objects reduce via ToPrimitive (which for our heap objects is always their string toString), so [0] == "0" is true (string compare of "0") but [0] == "" is false — never a number coercion of the object.

pub fn arith( &mut self, op: NumOp, a: &Value, b: &Value, ) -> Result<Value, String>

The numeric-hook arithmetic/relational fallback for non-native operands (called by fusevm when at least one operand isn’t Int/Float).

pub fn bitwise(&self, tag: i64, a: &Value, b: &Value) -> Value

Bitwise/shift ops with JS ToInt32/ToUint32 semantics.

impl JsHost

pub fn iter_vec(&mut self, v: &Value) -> Result<Vec<Value>, String>

Collect an iterable into a vector of values (arrays and strings).

pub fn enum_keys(&mut self, v: &Value) -> Vec<Value>

Enumerable keys of an object/array (for for-in).

Trait Implementations

impl Default for JsHost

fn default() -> Self

Returns the “default value” for a type.