Struct boa::environment::function_environment_record::FunctionEnvironmentRecord

pub struct FunctionEnvironmentRecord {
    pub env_rec: HashMap<String, DeclerativeEnvironmentRecordBinding>,
    pub this_value: Value,
    pub this_binding_status: BindingStatus,
    pub function_object: Value,
    pub home_object: Value,
    pub new_target: Value,
    pub outer_env: Option<Environment>,
}

https://tc39.github.io/ecma262/#table-16

Fields

env_rec: HashMap<String, DeclerativeEnvironmentRecordBinding>

this_value: Value

This is the this value used for this invocation of the function.

this_binding_status: BindingStatus

If the value is "lexical", this is an ArrowFunction and does not have a local this value.

function_object: Value

The function object whose invocation caused this Environment Record to be created.

home_object: Value

If the associated function has super property accesses and is not an ArrowFunction, [[HomeObject]] is the object that the function is bound to as a method. The default value for [[HomeObject]] is undefined.

new_target: Value

If this Environment Record was created by the [[Construct]] internal method, [[NewTarget]] is the value of the [[Construct]] newTarget parameter. Otherwise, its value is undefined.

outer_env: Option<Environment>

Reference to the outer environment to help with the scope chain Option type is needed as some environments can be created before we know what the outer env is

Methods

impl FunctionEnvironmentRecord

pub fn bind_this_value(&mut self, value: Value)

pub fn get_this_binding(&self) -> Value

Trait Implementations

impl EnvironmentRecordTrait for FunctionEnvironmentRecord

fn has_binding(&self, name: &String) -> bool

Determine if an Environment Record has a binding for the String value N. Return true if it does and false if it does not.

fn create_mutable_binding(&mut self, name: String, deletion: bool)

Create a new but uninitialized mutable binding in an Environment Record. The String value N is the text of the bound name. If the Boolean argument deletion is true the binding may be subsequently deleted.

fn create_immutable_binding(&mut self, name: String, strict: bool)

Create a new but uninitialized immutable binding in an Environment Record. The String value N is the text of the bound name. If strict is true then attempts to set it after it has been initialized will always throw an exception, regardless of the strict mode setting of operations that reference that binding.

fn initialize_binding(&mut self, name: String, value: Value)

Set the value of an already existing but uninitialized binding in an Environment Record. The String value N is the text of the bound name. V is the value for the binding and is a value of any ECMAScript language type.

fn set_mutable_binding(&mut self, name: String, value: Value, strict: bool)

Set the value of an already existing mutable binding in an Environment Record. The String value name is the text of the bound name. value is the value for the binding and may be a value of any ECMAScript language type. S is a Boolean flag. If strict is true and the binding cannot be set throw a TypeError exception.

fn get_binding_value(&self, name: String, _strict: bool) -> Value

Returns the value of an already existing binding from an Environment Record. The String value N is the text of the bound name. S is used to identify references originating in strict mode code or that otherwise require strict mode reference semantics.

fn delete_binding(&mut self, name: String) -> bool

Delete a binding from an Environment Record. The String value name is the text of the bound name. If a binding for name exists, remove the binding and return true. If the binding exists but cannot be removed return false. If the binding does not exist return true.

fn has_super_binding(&self) -> bool

Determine if an Environment Record establishes a super method binding. Return true if it does and false if it does not.

fn has_this_binding(&self) -> bool

Determine if an Environment Record establishes a this binding. Return true if it does and false if it does not.

fn with_base_object(&self) -> Value

If this Environment Record is associated with a with statement, return the with object. Otherwise, return undefined.

fn get_outer_environment(&self) -> Option<Environment>

Get the next environment up

fn set_outer_environment(&mut self, env: Environment)

Set the next environment up

fn get_environment_type(&self) -> EnvironmentType

Get the type of environment this is

fn get_global_object(&self) -> Option<Value>

Fetch global variable

impl Drop for FunctionEnvironmentRecord

fn drop(&mut self)

Executes the destructor for this type.

impl Clone for FunctionEnvironmentRecord

fn clone(&self) -> FunctionEnvironmentRecord

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Trace for FunctionEnvironmentRecord

unsafe fn trace(&self)

Marks all contained Gcs.

unsafe fn root(&self)

Increments the root-count of all contained Gcs.

unsafe fn unroot(&self)

Decrements the root-count of all contained Gcs.

fn finalize_glue(&self)

Runs Finalize::finalize() on this object and all contained subobjects

impl Finalize for FunctionEnvironmentRecord

fn finalize(&self)