dowdiness/js_engine/interpreter/runtime does not have a README file
ExecutorActivationFrame
pub(open) trait ExecutorActivationFrame {
fn step(Self, Interpreter) -> ExecutorActivationStep raise
fn deliver_activation_completion(Self, ExecutorActivationCompletion) -> Unit raise
}ExecutorCode
pub(open) trait ExecutorCode {
fn start(Self, Interpreter, PreparedExecutorActivation) -> &ExecutorActivationFrame raise
}GeneratorReturnSignal
Generator return signal — used to inject return at yield point
This is NOT JS-catchable, but must trigger finally blocks.
JsonBridgeError
Internal failure used by the stable Engine JSON boundary.
YieldSignal
Yield signal — used to suspend generator execution
ArrayBufferState
ArrayData
pub(all) struct ArrayData {
elements : Array[Value]
bag : PropertyBag
length_writable : Bool
holes : Map[Int, Unit]
extensible : Bool
}Binding
pub(all) struct Binding {
value : Value
kind : BindingKind
initialized : Bool
annex_b_hoisted : Bool
is_parameter : Bool
}BuiltinCtorPrototypeInstall
pub(all) enum BuiltinCtorPrototypeInstall {
FrozenAtInstall
PreBagged
AssignAtInstall
}How the constructor object's .prototype property is prepared before the
cache-for-X install pins proto and registers ctor in env.
CallContext
Callable
pub(all) enum Callable {
UserFunc(FuncData)
ArrowFunc(FuncData)
UserFuncExt(FuncDataExt)
ArrowFuncExt(FuncDataExt)
NativeCallable(String, (Array[Value]) -> Value raise)
NativeCallableWithContext(String, (CallContext, Array[Value]) -> Value raise)
NonConstructableCallable(String, (Array[Value]) -> Value raise)
BoundFunc(Value, Value, Array[Value])
FuncCallMethod(Value)
FuncApplyMethod(Value)
MethodCallable(String, (Value, Array[Value]) -> Value raise)
InterpreterCallable(String, (Interpreter, Value, Array[Value]) -> Value raise)
InterpreterCallableWithContext(String, (Interpreter, CallContext, Value, Array[Value]) -> Value raise)
ExecutorCallable(ExecutorCallableData)
NonConstructableInterpreterCallable(String, (Interpreter, Array[Value]) -> Value raise)
ConstructorOnlyCallable(String, (Interpreter, Array[Value]) -> Value raise)
ClassConstructor(ClassConstructorData)
}ClassConstructorData
pub(all) struct ClassConstructorData {
name : String
proto : Value
super_ctor : Value?
ctor_fn : (Array[Param], String?, Array[Stmt])?
closure : Environment
super_proto : Value
instance_fields : Array[ClassFieldInit]
private_instance_fields : Array[ClassFieldInit]
materializer : FunctionMaterializer?
source_text : String?
private_brand : Value
private_methods : Map[String, Value]
}ClassFieldInit
pub(all) struct ClassFieldInit {
key : Value
initializer : Expr?
closure : Environment
materializer : FunctionMaterializer?
}A single instance field initializer, captured at class definition time.
CompiledScriptEarlyErrorSettlement
pub struct CompiledScriptEarlyErrorSettlement {
// private fields
}CompiledScriptLexicalBinding
pub struct CompiledScriptLexicalBinding {
// private fields
}CompiledScriptLexicalBinding::CompiledScriptLexicalBinding
fn CompiledScriptLexicalBinding::CompiledScriptLexicalBinding(kind~ : BindingKind, name~ : String) -> CompiledScriptLexicalBindingCompiledScriptPreparation
pub struct CompiledScriptPreparation {
// private fields
}CompiledScriptPreparation::CompiledScriptPreparation
fn CompiledScriptPreparation::CompiledScriptPreparation(strict~ : Bool, var_names~ : Array[String], function_names~ : Array[String], lexical_bindings~ : Array[CompiledScriptLexicalBinding]) -> CompiledScriptPreparationCompiledScriptPreparation::with_early_error_settlement
fn CompiledScriptPreparation::with_early_error_settlement(strict~ : Bool, var_names~ : Array[String], function_names~ : Array[String], lexical_bindings~ : Array[CompiledScriptLexicalBinding], settlement~ : CompiledScriptEarlyErrorSettlement) -> CompiledScriptPreparationConsoleOutputKind
pub(all) enum ConsoleOutputKind {
Log
Debug
Info
Warn
Error
}Stable category of Realm-independent console output.
Environment
pub(all) struct Environment {
bindings : Map[String, Binding]
parent : Environment?
is_var_scope : Bool
with_object : Value?
realm_state : RealmState?
interpreter_context : Interpreter?
error_class_names : Map[String, Unit]
markers : Map[String, Bool]
}Environment::assign
Environment::assign_var
Assign to the nearest var-compatible binding with the given name, skipping
real let/const bindings in intervening scopes. This is needed for eval'd var
declarations that must target the function scope's var or parameter binding,
even when a block-scoped let/const shadows the name in between.
Environment::def
fn Environment::def(self : Environment, name : String, value : Value, kind : BindingKind) -> Unit raiseEnvironment::def_builtin
Environment::def_const_tdz_if_absent
Ensure a local const binding exists without exposing BindingKind to the
compiler's indexed-slot path.
Environment::def_let_tdz_if_absent
Ensure a local let binding exists without exposing BindingKind to the
compiler's indexed-slot path.
Environment::def_param_tdz
Define an uninitialized parameter TDZ binding. Used by the parameter
pre-pass (§10.2.11 step 21) so self/forward-referring defaults throw
ReferenceError rather than resolving the outer scope's binding.
Environment::def_parameter
Define a function parameter binding. Parameters are stored as
LetBinding with is_parameter: true so the Annex B block-level
function extension can distinguish them from real let declarations.
Environment::def_tdz
Define a TDZ binding (let/const before initialization)
Environment::find_var_env
Walk up the scope chain to find the nearest variable environment
(function or global scope where var declarations are hoisted to).
Environment::find_with_object
Find the with-object for a name (walking up env chain to find a with env containing this name)
Environment::has_var
Walk up the scope chain to find a var-compatible binding with the given
name. Formal parameters are included because sloppy function-body var
declarations may redeclare and update mapped parameter bindings.
Environment::initialize
Initialize a TDZ binding (when declaration is executed)
Environment::initialize_in_chain
Walk the scope chain to find an existing binding for name and
initialize it with value. Unlike initialize, which only looks at
the local env, this climbs parents. Needed for super() to write
this back to the derived class's param env when body execution
happens in a separate body env (§10.2.11 split). For derived-constructor
TDZ this, the write follows BindThisValue and rejects a second
initialization.
Environment::resolve_slot
Resolve one local binding once for indexed bytecode access. The caller
retains the returned capability and must not repeat name lookup per op.
EnvironmentSlot
pub struct EnvironmentSlot {
// private fields
}An opaque capability for one local environment binding. The capability
retains the binding cell itself, so captured activations and direct eval
observe the same mutable identity without exposing Binding's fields.
EnvironmentSlot::assign
Assign an already initialized binding, enforcing TDZ and const semantics
at the runtime boundary while retaining the shared cell identity.
EnvironmentSlot::initialize
Initialize a declaration's TDZ cell. Initialization is distinct from
assignment so the runtime, rather than bytecode, owns declaration state.
EnvironmentSlot::read
Read a binding through its runtime-owned capability, preserving TDZ
diagnostics and the exact cell identity captured by the environment.
ExecContext
Immutable per-call execution context passed through the evaluation pipeline.
Replaces the mutable strict and current_generator fields that were
previously on the Interpreter struct, eliminating fragile save/restore patterns.
ExecutionPolicy
pub(all) struct ExecutionPolicy {
// private fields
}Public, immutable policy inputs for an explicitly bounded evaluation.
The fields remain private so callers can only obtain validated values.
ExecutionPolicy::new
fn ExecutionPolicy::new(step_budget : Int64, stack_depth_limit : Int64, interruption : InterruptionHandle) -> Result[ExecutionPolicy, ExecutionPolicyError]ExecutionPolicyError
pub(all) struct ExecutionPolicyError {
// private fields
}Opaque validation details for an invalid bounded-evaluation policy.
ExecutionPolicyError::message
ExecutionPolicyError::parameter_code
ExecutorActivationCapabilitySummary
pub struct ExecutorActivationCapabilitySummary {
// private fields
}ExecutorActivationCompletion
pub enum ExecutorActivationCompletion {
ExecutorActivationCompletionNormal(Value)
ExecutorActivationCompletionAbrupt(Error)
ExecutorActivationCompletionReference(ResolvedBindingReference)
}ExecutorActivationStep
pub enum ExecutorActivationStep {
ExecutorActivationContinue
ExecutorActivationNormal(Value)
ExecutorActivationReturn(Value)
ExecutorActivationCall(ExecutorCallRequest)
ExecutorActivationConstruct(ExecutorConstructRequest)
ExecutorActivationPropertyGet(ExecutorPropertyGetRequest)
ExecutorActivationPropertyKey(ExecutorPropertyKeyRequest)
ExecutorActivationComputedPropertyGet(ExecutorComputedPropertyGetRequest)
ExecutorActivationPropertySet(ExecutorPropertySetRequest)
ExecutorActivationPropertyUpdate(ExecutorPropertyUpdateRequest)
ExecutorActivationCoercingAddition(ExecutorCoercingAdditionRequest)
ExecutorActivationCoercingRelational(ExecutorCoercingRelationalRequest)
ExecutorActivationCoercingSubtraction(ExecutorCoercingSubtractionRequest)
ExecutorActivationCoercingMultiplicative(ExecutorCoercingMultiplicativeRequest)
ExecutorActivationNumericConversion(ExecutorNumericConversionRequest)
ExecutorActivationPropertyDelete(ExecutorPropertyDeleteRequest)
ExecutorActivationIterableSpread(ExecutorIterableSpreadRequest)
ExecutorActivationCopyDataProperties(ExecutorCopyDataPropertiesRequest)
ExecutorActivationBinding(ExecutorBindingRequest)
ExecutorActivationBindingReference(ExecutorBindingReferenceRequest)
ExecutorActivationBindingReferenceAccess(ExecutorBindingReferenceAccessRequest)
ExecutorActivationBindingUpdate(ExecutorBindingUpdateRequest)
ExecutorActivationReference(ResolvedBindingReference)
}ExecutorBindingReferenceAccessRequest
pub struct ExecutorBindingReferenceAccessRequest {
// private fields
}ExecutorBindingReferenceRequest
pub struct ExecutorBindingReferenceRequest {
// private fields
}ExecutorBindingStart
pub enum ExecutorBindingStart {
ExecutorBindingCompleted(Value)
ExecutorBindingSuspended(ExecutorBindingRequest)
}ExecutorBindingUpdateStart
pub enum ExecutorBindingUpdateStart {
ExecutorBindingUpdateCompleted(Value)
ExecutorBindingUpdateSuspended(ExecutorBindingUpdateRequest)
}ExecutorCallableData
pub struct ExecutorCallableData {
// private fields
}ExecutorCallableData::is_constructable
ExecutorCallableData::length
ExecutorCallableData::name
ExecutorCallableData::source_text
ExecutorCallableData::start_frame
fn ExecutorCallableData::start_frame(self : ExecutorCallableData, interp : Interpreter, prepared : PreparedExecutorActivation) -> &ExecutorActivationFrame raiseExecutorCoercingAdditionRequest
pub struct ExecutorCoercingAdditionRequest {
// private fields
}ExecutorCoercingAdditionStart
pub enum ExecutorCoercingAdditionStart {
ExecutorCoercingAdditionCompleted(Value)
ExecutorCoercingAdditionSuspended(ExecutorCoercingAdditionRequest)
}ExecutorCoercingLessThanOrEqualRequest
pub struct ExecutorCoercingLessThanOrEqualRequest {
// private fields
}ExecutorCoercingLessThanOrEqualStart
pub enum ExecutorCoercingLessThanOrEqualStart {
ExecutorCoercingLessThanOrEqualCompleted(Value)
ExecutorCoercingLessThanOrEqualSuspended(ExecutorCoercingLessThanOrEqualRequest)
}ExecutorCoercingMultiplicativeRequest
pub struct ExecutorCoercingMultiplicativeRequest {
// private fields
}ExecutorCoercingMultiplicativeStart
pub enum ExecutorCoercingMultiplicativeStart {
ExecutorCoercingMultiplicativeCompleted(Value)
ExecutorCoercingMultiplicativeSuspended(ExecutorCoercingMultiplicativeRequest)
}ExecutorCoercingRelationalRequest
pub struct ExecutorCoercingRelationalRequest {
// private fields
}ExecutorCoercingRelationalStart
pub enum ExecutorCoercingRelationalStart {
ExecutorCoercingRelationalCompleted(Value)
ExecutorCoercingRelationalSuspended(ExecutorCoercingRelationalRequest)
}ExecutorCoercingSubtractionRequest
pub struct ExecutorCoercingSubtractionRequest {
// private fields
}ExecutorCoercingSubtractionStart
pub enum ExecutorCoercingSubtractionStart {
ExecutorCoercingSubtractionCompleted(Value)
ExecutorCoercingSubtractionSuspended(ExecutorCoercingSubtractionRequest)
}ExecutorComputedCallPreparationStart
pub enum ExecutorComputedCallPreparationStart {
ExecutorComputedCallPreparationCompleted(Value)
ExecutorComputedCallPreparationSuspended(ExecutorComputedPropertyGetRequest)
}ExecutorComputedPropertyGetRequest
pub struct ExecutorComputedPropertyGetRequest {
// private fields
}ExecutorComputedPropertyGetStart
pub enum ExecutorComputedPropertyGetStart {
ExecutorComputedPropertyGetCompleted(Value)
ExecutorComputedPropertyGetSuspended(ExecutorActivationStep)
}ExecutorComputedPropertySetStart
pub enum ExecutorComputedPropertySetStart {
ExecutorComputedPropertySetCompleted(Value)
ExecutorComputedPropertySetSuspended(ExecutorActivationStep)
}ExecutorCopyDataPropertiesRequest
pub struct ExecutorCopyDataPropertiesRequest {
// private fields
}ExecutorCopyDataPropertiesStart
pub enum ExecutorCopyDataPropertiesStart {
ExecutorCopyDataPropertiesCompleted
ExecutorCopyDataPropertiesSuspended(ExecutorCopyDataPropertiesRequest)
}ExecutorIterableSpreadStart
pub enum ExecutorIterableSpreadStart {
ExecutorIterableSpreadCompleted(Array[Value])
ExecutorIterableSpreadSuspended(ExecutorIterableSpreadRequest)
}ExecutorMultiplicativeOperator
pub(all) enum ExecutorMultiplicativeOperator {
ExecutorMultiplicativeMultiply
ExecutorMultiplicativeDivide
ExecutorMultiplicativeRemainder
}ExecutorNumericConversionRequest
pub struct ExecutorNumericConversionRequest {
// private fields
}ExecutorNumericConversionStart
pub enum ExecutorNumericConversionStart {
ExecutorNumericConversionCompleted(Value)
ExecutorNumericConversionSuspended(ExecutorNumericConversionRequest)
}ExecutorPropertyDeleteStart
pub enum ExecutorPropertyDeleteStart {
ExecutorPropertyDeleteCompleted(Value)
ExecutorPropertyDeleteSuspended(ExecutorPropertyDeleteRequest)
}ExecutorPropertyKeyStart
pub enum ExecutorPropertyKeyStart {
ExecutorPropertyKeyCompleted(Value)
ExecutorPropertyKeySuspended(ExecutorPropertyKeyRequest)
}ExecutorRelationalOperator
pub(all) enum ExecutorRelationalOperator {
ExecutorRelationalLessThan
ExecutorRelationalGreaterThan
ExecutorRelationalGreaterThanOrEqual
ExecutorRelationalLessThanOrEqual
}FuncData
pub(all) struct FuncData {
name : String?
params : Array[String]
body : Array[Stmt]
closure : Environment
strict : Bool
has_name_binding : Bool
is_method : Bool
source_text : String?
materializer : FunctionMaterializer?
}FuncDataExt
pub(all) struct FuncDataExt {
name : String?
params : Array[Param]
rest_param : String?
body : Array[Stmt]
closure : Environment
strict : Bool
has_name_binding : Bool
is_method : Bool
source_text : String?
materializer : FunctionMaterializer?
}FunctionExecutionHooks
pub struct FunctionExecutionHooks {
// private fields
}FunctionExecutionHooks::FunctionExecutionHooks
fn FunctionExecutionHooks::FunctionExecutionHooks(start~ : () -> Unit raise, complete~ : (Bool) -> Unit raise) -> FunctionExecutionHooksFunctionMaterializationForm
pub(all) enum FunctionMaterializationForm {
FunctionDeclaration
FunctionExpression
NamedFunctionExpression
MethodFunction
ComputedMethodFunction
ArrowFunction
} derive(Eq)FunctionMaterializationForm::equal
fn FunctionMaterializationForm::equal(FunctionMaterializationForm, FunctionMaterializationForm) -> BoolFunctionMaterializationForm::not_equal
fn FunctionMaterializationForm::not_equal(x : FunctionMaterializationForm, y : FunctionMaterializationForm) -> BoolFunctionMaterializationParameters
FunctionMaterializationRequest
pub struct FunctionMaterializationRequest {
form : FunctionMaterializationForm
site : Loc
name : String?
parameters : FunctionMaterializationParameters
body : Array[Stmt]
closure : Environment
strict : Bool
source_text : String?
}FunctionMaterializationRequest::FunctionMaterializationRequest
fn FunctionMaterializationRequest::FunctionMaterializationRequest(form~ : FunctionMaterializationForm, site~ : Loc, name~ : String?, parameters~ : FunctionMaterializationParameters, body~ : Array[Stmt], closure~ : Environment, strict~ : Bool, source_text~ : String?) -> FunctionMaterializationRequestFunctionMaterializer
pub struct FunctionMaterializer {
// private fields
}FunctionMaterializer::FunctionMaterializer
fn FunctionMaterializer::FunctionMaterializer(begin~ : () -> FunctionMaterializer, materialize~ : (Interpreter, FunctionMaterializationRequest) -> Value raise, hooks? : FunctionExecutionHooks?) -> FunctionMaterializerFunctionRealmProtos
FunctionRealmProtos::FunctionRealmProtos
fn FunctionRealmProtos::FunctionRealmProtos(function_proto? : Value?, object_proto? : Value?, string_proto? : Value?, number_proto? : Value?, boolean_proto? : Value?, symbol_proto? : Value?, array_proto? : Value?, map_proto? : Value?, set_proto? : Value?, promise_proto? : Value?, constructor_prototype_registry? : Value?) -> FunctionRealmProtosGenState
pub(all) enum GenState {
SuspendedStart
Executing
SuspendedYield
Completed
}Generator state machine
GeneratorObject
pub(all) struct GeneratorObject {
id : Int
state : GenState
body : Array[Stmt]
strict : Bool
params : Array[String]
params_ext : Array[Param]?
rest_param : String?
closure : Environment
is_async : Bool
name : String?
interpreter : Interpreter
args : Array[Value]
this_val : Value
env : Environment?
pc : Int
yield_value : Value
resuming : Bool
resume_action : ResumeAction
try_resume_phase : Int
try_resume_yield_base : Int
try_resume_error : Value
try_resume_result : Signal
try_resume_pending_error : Error?
loop_env_stack : Array[Environment]
loop_yield_base_stack : Array[Int]
stmt_resume_index_stack : Array[Int]
stmt_resume_env_stack : Array[Environment]
stmt_resume_value_stack : Array[Value]
for_of_iterator : Value
for_of_next : Value
for_of_iterator_stack : Array[Value]
for_of_next_stack : Array[Value]
for_of_resume : Bool
for_of_awaiting_next : Bool
dstr_iterator_stack : Array[Value]
delegate_iterator : Value
delegate_next : Value
delegating : Bool
yield_index : Int
resume_at_yield : Int
yield_resume_values : Map[Int, Value]
}Generator object stored as internal data on an ObjectData
HostEnv
pub(all) struct HostEnv {
output : Array[String]
console_output_sink : (ConsoleOutputKind, String) -> Unit raise?
microtask_queue : Array[Microtask]
timer_queue : PriorityQueue[TimerTask]
timer_id_counter : Ref[Int]
timer_insertion_counter : Ref[Int]
cancelled_timer_ids : Map[Int, Bool]
module_loader : ModuleLoader?
}Host environment state — concerns that belong to the runtime container
rather than the JavaScript execution model itself.
Separating these fields makes the engine/host boundary explicit and
enables future host-environment variations (different I/O, timer
semantics, or module resolution) without touching execution internals.
HostEnv::emit_console_output
fn HostEnv::emit_console_output(self : HostEnv, kind : ConsoleOutputKind, text : String) -> Unit raiseDeliver console output to the configured Host destination. Interpreters
without a destination retain the legacy compatibility buffer instead.
HostSlotKey
Embedder-owned slot identity. Construct only via HostSlotKey::reserve.
HostSlotKey::reserve
Allocate a unique key within this loaded runtime package instance.
Aborts if the allocator is exhausted — never wraps.
InternalSlotKey
pub(all) enum InternalSlotKey {
StringData
NumberData
BooleanData
SymbolData
PrimitiveValue
ArrayLength
TypedArrayName
ViewedArrayBuffer
ArrayBufferID
ByteOffset
ByteLength
ArrayBufferByteLength
DateValue
ExportName
NamespaceObject
ExportValue
SyncIterator
SyncNextMethod
SourceText
PrivateBrandStore
} derive(Eq, Hash, Debug)InternalSlotKey::hash_combine
InternalSlotKey::not_equal
Interpreter
pub(all) struct Interpreter {
host : HostEnv
global : Environment
global_this : Value
annex_b : Bool
realm_state : RealmState
module_registry : Map[String, Map[String, Value]]
module_exports : Map[String, Value]
module_export_bindings : Array[(String, String)]
generator_objects : Map[Int, GeneratorObject]
gen_id_counter : Ref[Int]
symbols : SymbolState
stdlib_hooks : StdlibHooks
in_nonarrow_param_default_eval : Bool
param_default_eval_var_conflicts : Set[String]?
active_function_materializer : FunctionMaterializer?
}Interpreter::array_define_own_property
fn Interpreter::array_define_own_property(self : Interpreter, arr : ArrayData, key : Value, partial : PartialDescriptor, loc : Loc) -> Bool raiseES §10.4.2.1 Array exotic [[DefineOwnProperty]]. Dispatches on:
- key == "length" -> array_set_length (§10.4.2.4 with partial truncation).
- key is array index -> ordinary-style write against bag, plus grow elements to idx+1 (ArraySetLength auto-grow) ONLY when descriptor is the default-data shape. Non-default (configurable:false / writable:false / enumerable:false) descriptors on indexed elements return false pending Stage C's per-index descriptor storage.
- Other keys -> ordinary-style write against arr.bag.
Interpreter::array_set_length
fn Interpreter::array_set_length(self : Interpreter, arr : ArrayData, partial : PartialDescriptor) -> Bool raiseES §10.4.2.4 ArraySetLength. The partial truncation loop is the
crux of this algorithm — see the Learn by Doing contribution point.
Interpreter::assign_compiled_name
fn Interpreter::assign_compiled_name(self : Interpreter, ctx : ExecContext, env : Environment, name : String, value : Value) -> Value raiseAssign an identifier for compiled execution without duplicating global
object, strict-mode, or implicit-global assignment rules in the compiler.
Interpreter::call_direct_eval_or_shadowed
fn Interpreter::call_direct_eval_or_shadowed(self : Interpreter, callee : Value, args : Array[Value], env : Environment, loc : Loc, caller_strict~ : Bool) -> Value raiseInterpreter::call_value
fn Interpreter::call_value(self : Interpreter, callee : Value, this_val : Value, args : Array[Value], loc : Loc) -> Value raiseInterpreter::construct_value
fn Interpreter::construct_value(self : Interpreter, ctor : Value, args : Array[Value], loc : Loc, proto_override? : Value?, new_target? : Value?) -> Value raiseInterpreter::copy_object_spread_properties
fn Interpreter::copy_object_spread_properties(self : Interpreter, target : Value, source : Value, loc : Loc) -> Unit raiseInterpreter::define_compiled_binding
fn Interpreter::define_compiled_binding(self : Interpreter, env : Environment, kind : VarKind, name : String, value : Value, has_initializer : Bool) -> Unit raiseInterpreter::define_own_property
fn Interpreter::define_own_property(self : Interpreter, val : Value, key : Value, partial : PartialDescriptor, loc : Loc) -> Bool raiseES [[DefineOwnProperty]] dispatcher — routes Proxy targets through the
defineProperty trap (proxy_define_property), others through
ordinary_define_own_property. This is the main entry point builtins
and internal callers should use.
Interpreter::define_simple_arguments_object
fn Interpreter::define_simple_arguments_object(self : Interpreter, env : Environment, args : Array[Value], callee : Value, strict : Bool, params : Array[String]) -> Unit raiseInterpreter::define_unmapped_arguments_object
fn Interpreter::define_unmapped_arguments_object(self : Interpreter, env : Environment, args : Array[Value], callee : Value, strict : Bool) -> Unit raiseInterpreter::delete_property_key
fn Interpreter::delete_property_key(self : Interpreter, obj : Value, key : Value, strict? : Bool) -> Bool raiseInterpreter::enqueue_microtask
fn Interpreter::enqueue_microtask(self : Interpreter, callback : Value, args : Array[Value]) -> UnitEnqueue a microtask to be executed when the current execution context completes.
This implements HostEnqueuePromiseJob from the ECMAScript spec.
Interpreter::eval_destructure_assign
fn Interpreter::eval_destructure_assign(self : Interpreter, ctx : ExecContext, pattern : Pattern, value : Value, env : Environment) -> Value raiseInterpreter::eval_destructure_assign_plan
fn Interpreter::eval_destructure_assign_plan(self : Interpreter, ctx : ExecContext, plan : DestructurePlan, value : Value, env : Environment) -> Value raiseInterpreter::eval_super_computed_call_reference
fn Interpreter::eval_super_computed_call_reference(self : Interpreter, env : Environment, key : Value, loc : Loc) -> (Value, Value) raiseInterpreter::eval_super_computed_property
fn Interpreter::eval_super_computed_property(self : Interpreter, env : Environment, key : Value, loc : Loc) -> Value raiseInterpreter::eval_super_property
fn Interpreter::eval_super_property(self : Interpreter, env : Environment, prop : String, loc : Loc) -> Value raiseInterpreter::eval_super_property_call_reference
fn Interpreter::eval_super_property_call_reference(self : Interpreter, env : Environment, prop : String, loc : Loc) -> (Value, Value) raiseInterpreter::eval_update_computed_property
fn Interpreter::eval_update_computed_property(self : Interpreter, ctx : ExecContext, obj : Value, key : Value, op : UpdateOp, prefix : Bool, member_loc : Loc, loc : Loc) -> Value raiseInterpreter::eval_update_property
fn Interpreter::eval_update_property(self : Interpreter, ctx : ExecContext, obj : Value, prop : String, op : UpdateOp, prefix : Bool, member_loc : Loc, loc : Loc) -> Value raiseInterpreter::get_cached_tagged_template_object
fn Interpreter::get_cached_tagged_template_object(self : Interpreter, key : String, quasis : Array[(String, String?)]) -> ValueInterpreter::get_compiled_name
fn Interpreter::get_compiled_name(self : Interpreter, env : Environment, name : String) -> Value raiseResolve an identifier for compiled execution using the same runtime
fallback as the tree-walking interpreter.
Interpreter::get_computed_property
fn Interpreter::get_computed_property(self : Interpreter, obj : Value, key : Value, loc : Loc) -> Value raiseInterpreter::get_iterator_next_method
fn Interpreter::get_iterator_next_method(self : Interpreter, iterator : Value, loc : Loc) -> Value raiseReturn an iterator's next method using the spec §7.4.1 [[Get]] path.
Per spec, callability is NOT checked here — GetIterator only gets the property.
The TypeError fires later in IteratorNext when Call(nextMethod, ...) is attempted.
Interpreter::get_own_property
fn Interpreter::get_own_property(self : Interpreter, val : Value, key : Value) -> (PropDescriptor, Value)? raiseES [[GetOwnProperty]] dispatcher — Proxy targets route through
proxy_get_own_property, TypedArrays synthesize integer-indexed element
descriptors per §10.4.5.1, and others route through
ordinary_get_own_property.
Returns (descriptor, value) pairs so the trap-provided value in the
Proxy case flows through (PropDescriptor has no value slot — the
value is stored separately on the bag or synthesized by the trap).
Interpreter::get_property
fn Interpreter::get_property(self : Interpreter, obj : Value, prop : String, loc : Loc) -> Value raiseInterpreter::get_property_key_with_receiver
fn Interpreter::get_property_key_with_receiver(self : Interpreter, target : Value, key : Value, receiver : Value, loc : Loc) -> Value raiseES [[Get]] with an explicit Receiver and an already-evaluated property-key
input. This is the shared receiver-aware boundary for ordinary objects and
every object-like Value variant. The key is canonicalized once at entry;
recursive prototype steps keep the resulting String/Symbol unchanged.
Interpreter::get_prototype_from_constructor
fn Interpreter::get_prototype_from_constructor(self : Interpreter, ctor : Value, loc : Loc) -> Value raiseInterpreter::has_property
Interpreter method: HasProperty with explicit interpreter context.
Interpreter::has_property_key
ES §7.3.11 HasProperty with a pre-computed property key.
Interpreter::iterator_close
IteratorClose(iteratorRecord, completion) for a non-throw completion.
Resolves "return" via [[Get]], calls it if present, and raises on
GetMethod/Call/IsObject failures (§7.4.11 steps 6–7). Use
iterator_close_throw when completion is a throw completion.
Interpreter::iterator_close_throw
IteratorClose(iteratorRecord, ThrowCompletion(...)) (§7.4.11 step 5).
Attempts return() for cleanup, then discards GetMethod/Call/IsObject
errors so the original ThrowCompletion remains the completion value.
Infallible: callers re-raise the original error after this returns.
Interpreter::iterator_result_value
fn Interpreter::iterator_result_value(self : Interpreter, iter_result : Value, loc : Loc) -> Value raisePerform IteratorValue(iterResult).
Interpreter::iterator_step_result
fn Interpreter::iterator_step_result(self : Interpreter, iterator : Value, next_method : Value, loc : Loc) -> Value? raisePerform IteratorStep(iteratorRecord).
Interpreter::iterator_step_value
fn Interpreter::iterator_step_value(self : Interpreter, iterator : Value, next_method : Value, loc : Loc) -> Value? raisePerform IteratorStep followed by IteratorValue.
Interpreter::new
fn Interpreter::new(annex_b? : Bool, module_loader? : ModuleLoader?, console_enabled? : Bool, console_output_sink? : (ConsoleOutputKind, String) -> Unit raise?, setup_builtins? : (Environment, Array[String], RealmState, Bool) -> Unit, setup_harness? : (Environment, Array[String], Value) -> Unit, stdlib_hooks? : StdlibHooks) -> InterpreterInterpreter::observe_execution_step
Interpreter::ordinary_define_own_property
fn Interpreter::ordinary_define_own_property(self : Interpreter, val : Value, key : Value, partial : PartialDescriptor, loc : Loc) -> Bool raiseES §10.1.6 OrdinaryDefineOwnProperty(O, P, Desc) + §10.4.2.1 Array
exotic dispatch + §10.4.5.3 IntegerIndexed exotic dispatch. Returns true
on success, false on rejection (the caller — Object.defineProperty
throws, Reflect.defineProperty returns false).
Interpreter::own_property_keys
Canonical [[OwnPropertyKeys]] (ES §10.1.11 + Array/String/Module/TypedArray
/Proxy exotic variants). Returns the own keys of val as String_/Symbol
Values in spec order: integer indices ascending, then insertion-order string
keys, then symbol keys. Array holes are omitted; TypedArray integer indices
surface; the Proxy variant runs the ownKeys trap. Every own-key consumer in
the runtime/stdlib routes through this op.
Interpreter::partial_descriptor_from_attrs
fn Interpreter::partial_descriptor_from_attrs(self : Interpreter, attrs : Value, loc : Loc) -> PartialDescriptor raiseES §6.2.5.5 ToPropertyDescriptor. Extract a PartialDescriptor from a JS
attrs object, invoking getters and reading inherited properties per spec.
Throws TypeError if:
- attrs is not an object
- both data (value/writable) and accessor (get/set) fields appear
- get or set is non-callable non-undefined
Interpreter::perform_eval
fn Interpreter::perform_eval(self : Interpreter, code : String, caller_env : Environment, direct : Bool, caller_strict? : Bool) -> Value raiseExecute eval code in a given environment.
If direct is true, executes in the caller's environment (direct eval).
If direct is false, executes in the global environment (indirect eval).
Handles strict mode isolation and var leaking per ES spec.
Per ES spec (18.2.1.1 PerformEval):
- Strict eval: all declarations (var, let, const, function) are isolated in a new scope
- Non-strict direct eval: var/function declarations leak to caller's variable environment, but let/const are isolated in a new eval lexical scope
- Non-strict indirect eval: var/function declarations leak to global scope, but let/const are isolated in a new eval lexical scope
Interpreter::prepare_executor_callable_call
fn Interpreter::prepare_executor_callable_call(self : Interpreter, executable : ExecutorCallableData, callee : Value, this_value : Value, args : Array[Value]) -> PreparedExecutorActivation raiseInterpreter::register_module
fn Interpreter::register_module(self : Interpreter, specifier : String, exports : Map[String, Value]) -> UnitRegister a module's exports in the module registry
Interpreter::reject_unobserved_native_progress
Interpreter::run_bounded
fn Interpreter::run_bounded(self : Interpreter, stmts : Array[Stmt], policy : ExecutionPolicy) -> Value raiseRun parsed source under one operation-scoped control carrier. The carrier
is installed and restored by the imperative shell around the existing run
path, so unbounded compatibility entry points remain unchanged.
Interpreter::run_compiled_script
fn Interpreter::run_compiled_script(self : Interpreter, stmts : Array[Stmt], eval : (ExecContext, Environment) -> Value raise) -> Value raiseInterpreter::run_executor_activation_coordinator
fn Interpreter::run_executor_activation_coordinator(self : Interpreter, root : &ExecutorActivationFrame) -> ExecutorActivationStep raiseInterpreter::run_materialized_function
fn[T] Interpreter::run_materialized_function(self : Interpreter, materializer : FunctionMaterializer?, thunk : () -> T raise) -> T raiseInterpreter::run_microtasks
Run all pending microtasks until the queue is empty.
This is called after each task (script execution) completes.
Implements the microtask checkpoint from WHATWG Event Loop spec.
Interpreter::run_microtasks_observed
fn Interpreter::run_microtasks_observed(self : Interpreter) -> Result[Unit, MicrotaskRunFailure] raiseRun all pending microtasks while retaining callback provenance on failure.
Interpreter::run_module
Run a module source and return its exports
Interpreter::run_modules
fn Interpreter::run_modules(self : Interpreter, modules : Array[(String, String)]) -> Map[String, Value] raiseRun multiple modules with all specifiers registered before evaluation.
The graph pass evaluates provided dependencies before importers while still
letting self-imports and simple cyclic fixtures resolve through the registry.
Interpreter::run_prepared_compiled_script
fn Interpreter::run_prepared_compiled_script(self : Interpreter, preparation : CompiledScriptPreparation, eval : (ExecContext, Environment) -> Value raise) -> Value raiseRun an already-compiled script body through the same script setup envelope
used by Interpreter::run.
Closure conversion lives outside the runtime package, but script execution
setup owns private runtime state: the active interpreter ref, static early
errors, declaration hoisting, and conversion of engine errors into JS
exceptions. Keeping that envelope here lets compiled execution share the
same boundary without exposing those internals.
Interpreter::run_timers
Run the event loop: process all pending timer tasks with
microtask checkpoints between each (per WHATWG event loop spec).
Timers are sorted by (delay, insertion_order) so they fire in the
correct relative order. After each timer callback, microtasks are
drained before the next timer fires.
For setInterval, the timer is re-enqueued after each invocation
until cancelled. A safety limit prevents infinite loops.
Interpreter::run_timers_observed
Run timers while retaining callback-vs-checkpoint context for direct
package dependents. Queue-policy defects still raise as internal failures.
Interpreter::run_with_function_materializer
fn Interpreter::run_with_function_materializer(self : Interpreter, stmts : Array[Stmt], materializer : FunctionMaterializer) -> Value raiseInterpreter::set_computed_property
fn Interpreter::set_computed_property(self : Interpreter, obj : Value, key : Value, value : Value, loc : Loc, strict? : Bool, receiver? : Value) -> Value raiseInterpreter::set_property
fn Interpreter::set_property(self : Interpreter, obj : Value, prop : String, value : Value, loc : Loc, strict? : Bool, receiver? : Value) -> Value raiseStage B.1 [[Set]] dispatcher.
receiver threads through the prototype chain and proxy fallbacks per
ES §10.1.9 (OrdinarySet) and §10.5.9 (ProxyExoticObject.[[Set]]).
- Inherited setters are invoked with receiver as this.
- Trap-less Proxy forwards to target.[[Set]](P, V, Receiver).
- When no own/inherited blocker exists and receiver !== obj, the write lands on receiver via define_value_on_receiver (approximating CreateDataProperty(Receiver, P, V) — a direct [[DefineOwnProperty]] that bypasses [[Set]], preventing the recursion loop that a naive self-call would produce for nested trap-less proxies).
Interpreter::spread_iterable
Spread an iterable value into an array of values using the iterator protocol
Interpreter::to_index
Interpreter method: ToIndex with explicit interpreter context.
Interpreter::to_js_string
Interpreter method: ToString with explicit interpreter context.
Interpreter::to_number
Interpreter method: ToNumber with explicit interpreter context.
Interpreter::to_object_literal_property_key
Interpreter::to_primitive_default
fn Interpreter::to_primitive_default(self : Interpreter, obj_val : Value, data : ObjectData) -> Value raiseInterpreter method: ToPrimitive (default hint) with explicit interpreter context.
Interpreter::to_primitive_value
Canonical ToPrimitive entry point for callers that hold an arbitrary
ECMAScript value. Primitive inputs pass through; object families that need
observable property access use the interpreter dispatchers.
Interpreter::typeof_compiled_name
fn Interpreter::typeof_compiled_name(self : Interpreter, ctx : ExecContext, env : Environment, name : String) -> Value raiseResolve typeof name for compiled and tree-walking execution using the
same identifier-reference semantics: unresolved names produce
"undefined", while TDZ bindings and a selected dynamic binding that
disappears during resolution still raise.
Interpreter::update_compiled_name
fn Interpreter::update_compiled_name(self : Interpreter, ctx : ExecContext, env : Environment, name : String, op : UpdateOp, prefix : Bool, loc : Loc) -> Value raiseUpdate an identifier for compiled execution while keeping strict-mode and
immutable-global behavior owned by the runtime.
Interpreter::validate_block_early_errors
fn Interpreter::validate_block_early_errors(_self : Interpreter, stmts : Array[Stmt], strict_context : Bool) -> Unit raiseInterpreter::with_active_value
Run a public runtime entry point with this interpreter installed as the
active realm for compatibility factory lookups.
Interpreter::with_execution_policy
fn[T] Interpreter::with_execution_policy(self : Interpreter, policy : ExecutionPolicy, action : () -> T raise) -> T raiseRun one internal operation under a fresh execution-control carrier.
Stable root-facade operations use this shell to keep one policy active
across multiple runtime phases without exposing the private control type.
Interpreter::with_function_materializer
fn[T] Interpreter::with_function_materializer(self : Interpreter, materializer : FunctionMaterializer?, thunk : () -> T raise) -> T raiseInterruptionHandle
pub(all) struct InterruptionHandle {
// private fields
}A monotonic, shared host interruption request.
InterruptionHandle::InterruptionHandle
InterruptionHandle::is_requested
MapData
Map data structure - stores key-value pairs with insertion order preservation
Uses SameValueZero for key comparison (NaN === NaN, +0 === -0)
Microtask
Microtask record for the event loop microtask queue
Stores a callback function and argument list to pass to it
MicrotaskRunFailure
pub struct MicrotaskRunFailure {
cause_ : Error
source_identity_ : String?
}A microtask-run failure paired with trustworthy callback provenance.
MicrotaskRunFailure::source_identity
ModuleLoader
Host-provided callback that resolves a module specifier to its exports.
Called by exec_import when a specifier is not already in module_registry.
Return a Map[String, Value] of exported names → values, or raise an error.
NumericUpdatePlan
pub struct NumericUpdatePlan {
// private fields
}NumericUpdatePlan::assigned_value
NumericUpdatePlan::expression_value
ObjectData
pub(all) struct ObjectData {
bag : PropertyBag
prototype : Value
callable : Callable?
class_name : String
extensible : Bool
arraybuffer_state : ArrayBufferState?
}PartialDescriptor
Partial property descriptor for VAP (§10.1.6.3 ValidateAndApplyPropertyDescriptor)
inputs. Each field is independently absent (None) or present (Some(_)),
distinct from the stored PropDescriptor where every attribute has a
concrete value. has_getter / has_setter disambiguate "field absent"
from "getter: undefined" since a user can write { get: undefined }.
PartialDescriptor::data_default
Build a PartialDescriptor representing ES §7.3.5 CreateDataPropertyOrThrow
— every data attribute explicit with defaults writable/enumerable/configurable = true.
Used by the [[Set]] landing rule §10.1.9.2 step 3.f.
PartialDescriptor::empty
Build a PartialDescriptor representing the "no attributes specified" case.
PartialDescriptor::is_accessor
ES §6.2.5.4 IsAccessorDescriptor: true iff either getter or setter is
explicitly present on the partial.
PartialDescriptor::is_data
ES §6.2.5.4 IsDataDescriptor: true iff either value or writable is
explicitly present on the partial.
PartialDescriptor::is_generic
ES §6.2.5.4 IsGenericDescriptor: neither data nor accessor — only
enumerable/configurable populated, or nothing at all.
PartialDescriptor::value_only
Build a PartialDescriptor with only value set. Used by the [[Set]]
landing rule §10.1.9.2 step 3.e (existing writable-data descriptor: call
[[DefineOwnProperty]] with just { [[Value]]: V }).
PreparedExecutorActivation
PreparedExecutorActivation::arguments
PreparedExecutorActivation::context
PreparedExecutorActivation::environment
PromiseData
pub(all) struct PromiseData {
state : PromiseState
result : Value
fulfill_reactions : Array[PromiseReaction]
reject_reactions : Array[PromiseReaction]
is_handled : Bool
bag : PropertyBag
extensible : Bool
prototype : Value?
}Promise data structure per ECMAScript spec
Promises have a state, result value, and queues of pending reactions
PromiseIntrinsics
Promise operations for builtins, independent of mutable global properties.
Capture the intrinsic constructor and prototype during realm setup.
PromiseIntrinsics::PromiseIntrinsics
PromiseIntrinsics::await_value
fn PromiseIntrinsics::await_value(self : PromiseIntrinsics, interp : Interpreter, value : Value, on_fulfill : Value, on_reject : Value) -> Unit raisePromiseResolve(%Promise%, value) followed by PerformPromiseThen.
Neither Promise.resolve nor a user-overridden Promise.prototype.then is read.
PromiseIntrinsics::new_capability
fn PromiseIntrinsics::new_capability(self : PromiseIntrinsics, interp : Interpreter) -> (Value, Value, Value)PromiseReaction
pub(all) struct PromiseReaction {
handler : Value?
resolve : Value
reject : Value
reaction_type : PromiseReactionType
}Promise reaction record - stores callbacks for promise resolution
Each reaction contains the handler (onFulfilled or onRejected) and the
dependent promise's resolve/reject capabilities
PromiseState
pub(all) enum PromiseState {
Pending
Fulfilled
Rejected
}Promise state per ECMAScript spec
PropDescriptor
PropertyBag
pub(all) struct PropertyBag {
properties : Map[String, Value]
symbol_properties : Map[Int, Value]
descriptors : Map[String, PropDescriptor]
symbol_descriptors : Map[Int, PropDescriptor]
internal_slots : Map[InternalSlotKey, Value]
host_slots : Map[Int, Value]
}Unified named/symbol property + descriptor storage embedded in every
exotic Value variant. Consolidates what used to be four parallel fields
so descriptor invariants are enforced in one place.
PropertyBag::PropertyBag
Construct an empty PropertyBag.
PropertyBag::delete_host_slot
PropertyBag::get_host_slot
PropertyBag::has_host_slot
PropertyBag::set_host_slot
ProxyData
Proxy data structure - wraps a target and handler for meta-programming
RealmState
pub(all) struct RealmState {
symbols : SymbolState
well_known_symbols : WellKnownSymbols
runtime_iterator_prototypes : RuntimeIteratorPrototypeCaches
active_overrides : Ref[FunctionRealmProtos?]
active_source_identity : Ref[String?]
constructor_prototype_registry : Value
observing_source_failure : Ref[Bool]
observed_source_failure : Ref[Error?]
observed_source_identity : Ref[String?]
object_prototype : Ref[Value?]
function_prototype : Ref[Value?]
string_prototype : Ref[Value?]
number_prototype : Ref[Value?]
boolean_prototype : Ref[Value?]
symbol_prototype : Ref[Value?]
array_prototype : Ref[Value?]
map_prototype : Ref[Value?]
set_prototype : Ref[Value?]
regexp_prototype : Ref[Value?]
promise_prototype : Ref[Value?]
weakmap_prototype : Ref[Value?]
weakset_prototype : Ref[Value?]
arraybuffer_state : ArrayBufferState
arraybuffer_id_counter : Ref[Int]
arraybuffer_store : Map[Int, Array[Int]]
detached_buffers : Map[Int, Bool]
weakmap_id_counter : Ref[Int]
weakmap_storage : Map[Int, Array[(Value, Value)]]
weakmap_id_table : Array[(ObjectData, Int)]
weakset_id_counter : Ref[Int]
weakset_storage : Map[Int, Array[Value]]
weakset_id_table : Array[(ObjectData, Int)]
// private fields
}RealmState::get_array_iterator_proto
Get or create the realm-owned %ArrayIteratorPrototype%.
RealmState::get_array_proto_values_intrinsic
RealmState::get_async_from_sync_iterator_proto
RealmState::get_async_iterator_proto
RealmState::get_iterator_proto
Get or create the realm-owned %IteratorPrototype%.
RealmState::get_string_iterator_proto
Get or create the realm-owned %StringIteratorPrototype%.
RealmState::make_array_entries_iterator_value
RealmState::make_array_iterator_value
RealmState::make_array_keys_iterator_value
RealmState::make_array_like_iterator_value
Create an array-like values iterator for objects with a length property.
RealmState::make_array_values_iterator_value
RealmState::make_string_iterator_value
RealmState::register_constructor_prototype
fn RealmState::register_constructor_prototype(self : RealmState, name : String, constructor_value : Value) -> UnitRecord a builtin constructor's intrinsic prototype in this realm's private
table. The table is shared by functions created before and after setup.
RealmState::set_array_proto_values_intrinsic
ResumeAction
Resume action for eval_yield to inspect when replaying
ResumeKind
How the generator was resumed
RuntimeIteratorPrototypeCaches
pub(all) struct RuntimeIteratorPrototypeCaches {
iterator_proto : Ref[Value?]
array_iterator_proto : Ref[Value?]
string_iterator_proto : Ref[Value?]
map_iterator_proto : Ref[Value?]
set_iterator_proto : Ref[Value?]
regexp_string_iterator_proto : Ref[Value?]
async_iterator_proto : Ref[Value?]
async_from_sync_iterator_proto : Ref[Value?]
}Lazy iterator prototype caches owned by a RealmState.
SetData
pub(all) struct SetData {
values : Array[Value]
tombstones : Set[Int]?
iteration_depth : Int
prototype : Value?
bag : PropertyBag
extensible : Bool
}Set data structure - stores unique values with insertion order preservation
Uses SameValueZero for value comparison (NaN === NaN, +0 === -0)
SetData::SetData
Construct SetData with values and an empty property bag (no expando properties).
Signal
SourceObservedFailure
pub struct SourceObservedFailure {
cause_ : Error
source_identity_ : String?
}A runtime failure paired with the deepest source identity that propagated
unchanged to the observation boundary.
SourceObservedFailure::cause
SourceObservedFailure::source_identity
StdlibHooks
pub(all) struct StdlibHooks {
get_string_method : (String, String, RealmState, Bool) -> Value
get_number_method : (Value, String, RealmState) -> Value
get_array_method_with_interp : (ArrayData, String, RealmState) -> Value
get_map_method : (MapData, String, RealmState) -> Value
get_set_method : (SetData, String, RealmState) -> Value
get_promise_method : (PromiseData, String, RealmState) -> Value
make_regexp_object : (RealmState, String, String) -> Value raise
typedarray_get_index : (ObjectData, Int, RealmState) -> Value
typedarray_set_index : (ObjectData, Int, Double, RealmState) -> Unit
typedarray_is_valid_index : (ObjectData, Int, RealmState) -> Bool
create_realm : () -> Interpreter
}Function pointer table for calling from runtime into stdlib.
This breaks the circular dependency: runtime defines the interface,
stdlib provides the implementation, root interpreter wires them together.
SymbolData
pub(all) struct SymbolData {
id : Int
description : String?
}Symbol data structure - each symbol has a unique ID and optional description
SymbolState
pub(all) struct SymbolState {
symbol_id_counter : Ref[Int]
all_symbols : Map[Int, SymbolData]
global_symbol_registry : Map[String, SymbolData]
symbol_registry_reverse : Map[Int, String]
well_known_symbols_cache : Ref[WellKnownSymbols?]
}Per-interpreter symbol state: ID counter, all-symbols table,
and the Symbol.for() / Symbol.keyFor() registry.
Passed through setup functions so that closures can capture it
without needing an Interpreter reference.
SymbolState::get_symbol_by_id
Get a symbol by its ID from this SymbolState.
SymbolState::new_symbol
Create a new symbol with a unique ID, registering it in this SymbolState.
SymbolState::well_known_symbols
TimerRunFailure
pub struct TimerRunFailure {
cause_ : Error
phase_ : TimerRunFailurePhase
source_identity_ : String?
}A timer-run failure paired atomically with the phase that observed it.
TimerRunFailure::phase
TimerRunFailure::source_identity
TimerRunFailurePhase
pub enum TimerRunFailurePhase {
TimerQueueDispatch
TimerCallback
IntervalCallback
MicrotaskCheckpoint
}Failure phase retained for the stable root facade's diagnostic adapter.
TimerTask
Timer task for setTimeout/setInterval (task queue per WHATWG spec)
Timers are processed one at a time with microtask checkpoints between each
Value
pub(all) enum Value {
Number(Double)
String_(String)
Bool(Bool)
Null
Undefined
Object(ObjectData)
Array(ArrayData)
Symbol(SymbolData)
Map(MapData)
Set(SetData)
Promise(PromiseData)
Proxy(ProxyData)
}WellKnownSymbols
pub(all) struct WellKnownSymbols {
iterator : SymbolData
async_iterator : SymbolData
has_instance : SymbolData
is_concat_spreadable : SymbolData
to_primitive : SymbolData
to_string_tag : SymbolData
match_sym : SymbolData
match_all : SymbolData
replace : SymbolData
search : SymbolData
species : SymbolData
split : SymbolData
unscopables : SymbolData
}Realm-owned well-known symbol identities.
These values are allocated from the realm's SymbolState before user code can
create symbols, preserving the existing well-known symbol IDs while moving
ownership out of per-symbol module globals.
apply_active_realm_protos
apply_array_literal_element
Append one evaluated element to an array literal accumulator.
apply_array_literal_hole
Append a single elision (hole) to an array literal accumulator: the index is
recorded as a hole and the slot is filled with undefined so that length
advances while in/iteration treat the index as absent.
apply_array_literal_spread
Append already-spread iterable values to an array literal accumulator. The
caller is responsible for running the iterator protocol (interpreter
semantics); this operation only lands the resulting values into storage.
apply_object_literal_accessor_property
apply_object_literal_data_property
apply_object_literal_proto_property
apply_object_literal_static_data_property
Set a static (compile-time string keyed) data property on an object literal
accumulator. Unlike apply_object_literal_data_property, this performs no
function-name inference: the bytecode lowering emits a separate
SetFunctionName instruction for static keys, so naming is already handled
upstream and must not be re-applied here.
array_species_create
ArraySpeciesCreate(originalArray, length) per ES spec 9.4.2.3
Looks up Symbol.species on the original array's constructor to determine
what constructor to use for the result. Returns a plain Array if no
custom species is found.
begin_executor_binding_assignment_load
fn begin_executor_binding_assignment_load(interp : Interpreter, ctx : ExecContext, env : Environment, name : String, loc : Loc) -> ExecutorBindingStart raisebegin_executor_binding_direct_eval
fn begin_executor_binding_direct_eval(interp : Interpreter, ctx : ExecContext, env : Environment, loc : Loc) -> ExecutorBindingStart raisebegin_executor_binding_load
fn begin_executor_binding_load(interp : Interpreter, ctx : ExecContext, env : Environment, name : String, loc : Loc) -> ExecutorBindingStart raisebegin_executor_binding_store
fn begin_executor_binding_store(interp : Interpreter, ctx : ExecContext, env : Environment, name : String, value : Value, loc : Loc) -> ExecutorBindingStart raisebegin_executor_binding_typeof
fn begin_executor_binding_typeof(interp : Interpreter, ctx : ExecContext, env : Environment, name : String, loc : Loc) -> ExecutorBindingStart raisebegin_executor_binding_update
fn begin_executor_binding_update(interp : Interpreter, ctx : ExecContext, env : Environment, name : String, op : UpdateOp, prefix : Bool, loc : Loc) -> ExecutorBindingUpdateStart raisebegin_executor_coercing_addition
fn begin_executor_coercing_addition(left : Value, right : Value, loc : Loc) -> ExecutorCoercingAdditionStart raisebegin_executor_coercing_less_than_or_equal
fn begin_executor_coercing_less_than_or_equal(left : Value, right : Value, loc : Loc) -> ExecutorCoercingLessThanOrEqualStart raisebegin_executor_coercing_multiplicative
fn begin_executor_coercing_multiplicative(operator : ExecutorMultiplicativeOperator, left : Value, right : Value, loc : Loc) -> ExecutorCoercingMultiplicativeStart raisebegin_executor_coercing_relational
fn begin_executor_coercing_relational(left : Value, right : Value, loc : Loc, operator : ExecutorRelationalOperator) -> ExecutorCoercingRelationalStart raisebegin_executor_coercing_subtraction
fn begin_executor_coercing_subtraction(left : Value, right : Value, loc : Loc) -> ExecutorCoercingSubtractionStart raisebegin_executor_computed_call_preparation
fn begin_executor_computed_call_preparation(target : Value, raw_key : Value, loc : Loc) -> ExecutorComputedCallPreparationStart raisebegin_executor_computed_property_get
fn begin_executor_computed_property_get(target : Value, raw_key : Value, loc : Loc) -> ExecutorComputedPropertyGetStart raisebegin_executor_computed_property_set
fn begin_executor_computed_property_set(target : Value, property_key : Value, value : Value, loc : Loc, strict : Bool) -> ExecutorComputedPropertySetStart raisebegin_executor_copy_data_properties
fn begin_executor_copy_data_properties(_interp : Interpreter, target : Value, source : Value, excluded_keys : Array[Value], loc : Loc) -> ExecutorCopyDataPropertiesStartbegin_executor_iterable_spread
begin_executor_numeric_conversion
fn begin_executor_numeric_conversion(interp : Interpreter, value : Value, loc : Loc) -> ExecutorNumericConversionStart raisebegin_executor_property_delete_computed
fn begin_executor_property_delete_computed(interp : Interpreter, target : Value, raw_key : Value, strict : Bool, loc : Loc) -> ExecutorPropertyDeleteStart raisebegin_executor_property_delete_static
fn begin_executor_property_delete_static(interp : Interpreter, target : Value, property_name : String, strict : Bool, loc : Loc) -> ExecutorPropertyDeleteStart raisebegin_executor_property_key
builtin_method_desc
Standard descriptor metadata for built-in prototype methods installed as
ordinary data properties.
call_callable_direct
Call a callable value, dispatching to the interpreter for UserFunc types.
Supports all callable types including user-defined functions.
Pass interp explicitly when user-code dispatch may be required.
check_proxy_set_trap_invariants
cleanup_holes_above_length
Drop hole entries at indices >= new_len after a length shrink.
Used by both Interpreter::set_property and
Interpreter::set_computed_property length-set paths to avoid the
near-identical 12-line block being kept in sync by hand.
Hole keys are Int (≤ 2^31-1); if new_len exceeds Int range, no
in-range hole can be out-of-range, so the cleanup is a no-op — we
skip it to avoid an overflowing Int64→Int cast.
collect_for_in_keys
compiled_script_preparation_matches
fn compiled_script_preparation_matches(preparation : CompiledScriptPreparation, strict : Bool, var_names : Array[String], function_names : Array[String], lexical_bindings : Array[CompiledScriptLexicalBinding], expected_settlement : CompiledScriptEarlyErrorSettlement, provenance_token? : Ref[Unit]?) -> Boolconstructor_realm_intrinsic_prototype
Resolve the intrinsic prototype selected by GetPrototypeFromConstructor's
primitive-prototype fallback. Proxy and bound-function traversal mirrors
GetFunctionRealm; revoked proxies therefore raise before any fallback.
create_data_property_or_throw
fn create_data_property_or_throw(interp : Interpreter, target : Value, index : Int64, value : Value) -> Unit raiseCreateDataPropertyOrThrow(O, P, V) per ES spec 7.3.5.
Sets an indexed property on a species result value and throws if
[[DefineOwnProperty]] rejects the creation.
create_iter_result
Create an iterator result object { value, done }
create_resolving_functions
Create resolve and reject capability functions for a promise.
Returns (resolve_func, reject_func).
default_stdlib_hooks
Default no-op hooks used before stdlib is wired in.
delete_array_like_element
Delete indexed element from array-like value
descriptor_to_value
Convert a stored PropDescriptor into a plain JS descriptor object for
Object.getOwnPropertyDescriptor / Reflect.getOwnPropertyDescriptor
callers. Emits value + writable for data descriptors; get + set for
accessor descriptors.
destructure_plan_array
fn destructure_plan_array(elements : Array[DestructurePlan?], rest : DestructurePlan?) -> DestructurePlandestructure_plan_object
fn destructure_plan_object(properties : Array[DestructurePropertyPlan], rest : DestructurePlan?) -> DestructurePlandestructure_plan_property
detach_keyed_collection_iterator_target
enqueue_promise_reaction_job
fn enqueue_promise_reaction_job(interp : Interpreter, reaction : PromiseReaction, argument : Value) -> UnitEnqueue a promise reaction job (microtask).
This implements NewPromiseReactionJob from ECMAScript spec.
eval_binary_op
eval_delete_computed_property
fn eval_delete_computed_property(interp : Interpreter, obj : Value, key : Value, strict : Bool) -> Value raiseeval_delete_identifier
fn eval_delete_identifier(interp : Interpreter, ctx : ExecContext, env : Environment, name : String) -> Value raiseeval_delete_property
fn eval_delete_property(interp : Interpreter, obj : Value, prop : String, strict : Bool) -> Value raiseeval_new_target_value
Resolve new.target from the current function environment. Scripts and
ordinary calls without a constructor binding match the tree-walker fallback
to undefined.
eval_this_value
Resolve this with the same TDZ-to-derived-constructor error mapping used
by expression evaluation. Compiled execution uses this helper instead of
treating this as an ordinary identifier.
eval_unary_value_op
fn eval_unary_value_op(op : UnaryOp, value : Value, loc : Loc, interp? : Interpreter?) -> Value raiseexecution_control_failure_code
fn execution_control_failure_code(error : Error) -> String?Translate private guardrail failures at the stable Engine boundary without
exposing the runtime error constructors through the root facade.
executor_activation_binding_reference_get
fn executor_activation_binding_reference_get(reference : ResolvedBindingReference) -> ExecutorActivationStepexecutor_activation_binding_reference_put
fn executor_activation_binding_reference_put(reference : ResolvedBindingReference, value : Value) -> ExecutorActivationStepexecutor_activation_binding_reference_resolution
fn executor_activation_binding_reference_resolution(ctx : ExecContext, env : Environment, name : String, loc : Loc) -> ExecutorActivationStep raiseexecutor_activation_binding_request
executor_activation_binding_update_request
fn executor_activation_binding_update_request(request : ExecutorBindingUpdateRequest) -> ExecutorActivationStepexecutor_activation_call
executor_activation_capability_summary_equal
fn executor_activation_capability_summary_equal(left : ExecutorActivationCapabilitySummary?, right : ExecutorActivationCapabilitySummary?) -> Boolexecutor_activation_coercing_addition
fn executor_activation_coercing_addition(left : Value, right : Value, loc : Loc) -> ExecutorActivationStepexecutor_activation_coercing_addition_request
fn executor_activation_coercing_addition_request(request : ExecutorCoercingAdditionRequest) -> ExecutorActivationStepexecutor_activation_coercing_less_than_or_equal
fn executor_activation_coercing_less_than_or_equal(left : Value, right : Value, loc : Loc) -> ExecutorActivationStepexecutor_activation_coercing_less_than_or_equal_request
fn executor_activation_coercing_less_than_or_equal_request(request : ExecutorCoercingLessThanOrEqualRequest) -> ExecutorActivationStepexecutor_activation_coercing_multiplicative
fn executor_activation_coercing_multiplicative(left : Value, right : Value, operator : ExecutorMultiplicativeOperator, loc : Loc) -> ExecutorActivationStepexecutor_activation_coercing_multiplicative_request
fn executor_activation_coercing_multiplicative_request(request : ExecutorCoercingMultiplicativeRequest) -> ExecutorActivationStepexecutor_activation_coercing_relational
fn executor_activation_coercing_relational(left : Value, right : Value, loc : Loc, operator : ExecutorRelationalOperator) -> ExecutorActivationStepexecutor_activation_coercing_relational_request
fn executor_activation_coercing_relational_request(request : ExecutorCoercingRelationalRequest) -> ExecutorActivationStepexecutor_activation_coercing_subtraction
fn executor_activation_coercing_subtraction(left : Value, right : Value, loc : Loc) -> ExecutorActivationStepexecutor_activation_coercing_subtraction_request
fn executor_activation_coercing_subtraction_request(request : ExecutorCoercingSubtractionRequest) -> ExecutorActivationStepexecutor_activation_completion_abrupt
executor_activation_completion_normal
executor_activation_computed_property_get_if_admitted
fn executor_activation_computed_property_get_if_admitted(target : Value, key : Value, loc : Loc) -> ExecutorActivationStep?executor_activation_computed_property_get_request
fn executor_activation_computed_property_get_request(request : ExecutorComputedPropertyGetRequest) -> ExecutorActivationStepexecutor_activation_construct
fn executor_activation_construct(ctor : Value, args : Array[Value], loc : Loc) -> ExecutorActivationStepexecutor_activation_copy_data_properties_request
fn executor_activation_copy_data_properties_request(request : ExecutorCopyDataPropertiesRequest) -> ExecutorActivationStepexecutor_activation_iterable_spread_request
fn executor_activation_iterable_spread_request(request : ExecutorIterableSpreadRequest) -> ExecutorActivationStepexecutor_activation_normal
executor_activation_numeric_conversion_request
fn executor_activation_numeric_conversion_request(request : ExecutorNumericConversionRequest) -> ExecutorActivationStepexecutor_activation_property_decrement
fn executor_activation_property_decrement(target : Value, property_name : String, prefix : Bool, member_loc : Loc, loc : Loc, strict : Bool) -> ExecutorActivationStepexecutor_activation_property_delete_request
fn executor_activation_property_delete_request(request : ExecutorPropertyDeleteRequest) -> ExecutorActivationStepexecutor_activation_property_get
fn executor_activation_property_get(target : Value, property_name : String, loc : Loc) -> ExecutorActivationStepexecutor_activation_property_increment
fn executor_activation_property_increment(target : Value, property_name : String, prefix : Bool, member_loc : Loc, loc : Loc, strict : Bool) -> ExecutorActivationStepexecutor_activation_property_key_request
fn executor_activation_property_key_request(request : ExecutorPropertyKeyRequest) -> ExecutorActivationStepexecutor_activation_property_set
fn executor_activation_property_set(target : Value, property_name : String, value : Value, loc : Loc, strict : Bool) -> ExecutorActivationStepexecutor_activation_return
executor_iterable_spread_batch_values
flatten_array_val
fulfill_promise
Fulfill a promise with the given value.
Triggers all fulfill reactions as microtasks.
get_array_iterator_override
fn get_array_iterator_override(arr : ArrayData, well_known_symbols~ : WellKnownSymbols) -> (Value?, Value?)get_array_like_element
Get indexed element from array-like value
get_array_like_element_interp
Get indexed element from array-like value using interpreter (handles user-defined getters)
get_assignment_name_value
get_function_length
Return the observable function length used by Function.prototype.bind.
Prefer an own numeric length property, falling back to callable metadata
for older function objects that synthesize length from their Callable tag.
get_keyed_collection_iterator_kind
get_keyed_collection_iterator_next_index
get_keyed_collection_iterator_target
get_private_field
Read a private field value from an object.
Returns the field value on success, raises TypeError if brand check fails.
get_proxy_handler
Get the handler of a proxy, throwing TypeError if revoked.
get_proxy_target
Get the target of a proxy, throwing TypeError if revoked.
get_proxy_trap
Get a trap function from the proxy handler, or None if the trap is not defined.
Throws TypeError if the proxy has been revoked.
Uses the engine's ordinary Get path (interp.get_property) so accessor traps
and proxy-handler proxies are resolved with full language semantics.
get_tostringtag_value
Get the Symbol.toStringTag value by walking the prototype chain.
Checks symbol properties and evaluates getter descriptors if present.
Per spec, errors thrown by @@toStringTag getters propagate to the caller.
has_array_like_element
Check if array-like value has indexed property.
interp is required so the Array branch can resolve %Array.prototype%
via get_array_prototype(interp.realm_state,data).
has_brand
Check if an object has been branded with the given private brand.
Returns false for non-object values (no TypeError).
has_parameter_expressions
§10.2.11 ContainsExpression / HasParameterExpressions for Ext
function parameter lists. True iff any param carries a default
initializer or a pattern that itself contains an expression
(nested default, computed key, or assignment target). A plain
destructuring pattern like {a} or [a, b] with no nested
initializers has NO expression per spec and must not trigger the
split; otherwise function f({a}) { var a; return a } would hoist
var a into body_env and shadow the destructured parameter.
Plain rest without a pattern is also not a parameter expression.
has_property
Look up a string-keyed property on an object, walking the prototype chain.
HasProperty: check if a named property exists on the object or its prototype chain
install_builtin_accessor
fn install_builtin_accessor(data : ObjectData, name : String, getter : Value?, setter : Value?) -> UnitInstall a built-in string-keyed accessor property.
At least one of getter / setter must be Some; (None, None) aborts.
Use None for an absent side (not Some(Undefined)), unless intentionally
mimicking a JS { get: undefined } / { set: undefined } descriptor.
install_builtin_frozen_data
Install a built-in string-keyed non-writable non-configurable data property.
install_builtin_method
Install a built-in string-keyed method and its standard method descriptor.
install_builtin_non_writable
Install a built-in string-keyed non-writable configurable data property.
install_builtin_symbol_accessor
Install a built-in symbol-keyed accessor property with no setter.
install_builtin_symbol_frozen_data
Install a built-in symbol-keyed non-writable non-configurable data property.
install_builtin_symbol_method
Install a built-in symbol-keyed method and its standard method descriptor.
install_builtin_symbol_string
Install a built-in symbol-keyed non-writable configurable string data property.
install_realm_pinned_builtin_constructor
fn install_realm_pinned_builtin_constructor(env : Environment, realm_proto_cache : Ref[Value?], ctor_name : String, ctor : Value, proto : Value, prototype_install? : BuiltinCtorPrototypeInstall, wire_proto_constructor? : Bool) -> UnitCache-for-X install contract (#504 / #512): atomically pin proto in the
realm dispatch cache (realm_proto_cache), prepare the constructor's
.prototype property per prototype_install, and register ctor in env.
Invariant: realm_proto_cache.val must equal the constructor object's
.prototype property in every realm. Splitting these updates causes silent
dual-source dispatch bugs (PR #138).
Set wire_proto_constructor when the family also needs
proto.constructor = ctor (Map/Set, Array, boxed primitives, Promise, …).
Migrated families: Map/Set, WeakMap/WeakSet, Array, Promise, boxed
primitives (String/Number/Boolean/Symbol). #512 rollout complete.
instanceof_prototype_chain
Helper for instanceof: walk prototype chain to check if l's prototype chain includes target_proto
is_array
§7.2.2 IsArray — returns true for Array exotic objects and Object values
whose class_name is "Array", recursively unwrapping Proxy chains.
Throws TypeError when a revoked Proxy is encountered (spec step 3.a).
is_constructor_value
Check if a Value is a constructor (has [[Construct]] internal method)
is_function_value
Check if a Value is a function (has a callable)
is_js_catchable_error
fn is_js_catchable_error(err : Error) -> BoolCheck if an error is a JavaScript catchable error
is_object_value
Check if a Value is an object per ES Type(v) is Object (§6.1.7).
Returns true for any Value variant that represents a JavaScript object
reference; false for language primitives (Number, String_, Bool, Null,
Undefined, Symbol, BigInt).
is_thenable_object_candidate
ES object-like values that participate in thenable assimilation.
is_typedarray_class
fn is_typedarray_class(name : String) -> BoolCheck if a class name corresponds to a TypedArray type.
js_error_to_throw_value
Convert a catchable error to the JS throw value used by this interpreter.
Runtime engine errors are surfaced as strings like "TypeError: ...".
js_error_to_value
Convert any catchable error to a JavaScript Error object Value
js_error_to_value_with_env
Convert any catchable error to a JavaScript Error object Value with proper prototype
json_to_realm_value
Copy MoonBit JSON into a realm without consulting the realm's global JSON
object or invoking JavaScript code.
lookup_symbol_property_chain
fn lookup_symbol_property_chain(obj_val : Value, data : ObjectData, sym_id : Int, interp? : Interpreter?) -> Value? raiseLook up a symbol-keyed property on an object, walking the prototype chain.
Also handles getter descriptors - invokes them and returns the result.
make_array
Wrap an Array[Value] in an Array Value with an empty property bag.
Dense-only arrays (no named props, no sparse length overrides) build via this.
make_array_with_holes
Wrap an Array[Value] and mark selected indices as array holes.
make_array_with_prototype
Wrap an Array[Value] with an explicit instance prototype.
Constructor adapters use this after resolving newTarget.prototype and
before exposing the newly allocated Array value.
make_bound_func
Create the shared object representation for an ECMAScript bound function.
prototype is the exact result of the target's [[GetPrototypeOf]]
operation (§10.4.1.3 BoundFunctionCreate), so Null must not be replaced
with the realm's Function.prototype.
make_canonical_proxy_constructor
make_classified_executor_arrow_function
fn[T : ExecutorCode] make_classified_executor_arrow_function(params : Array[String], closure : Environment, strict : Bool, code : T, source_body : Array[Stmt], rest_param? : String?) -> ValueExecutorCode providers are trusted to supply code corresponding to
source_body; runtime admission cannot prove otherwise.
make_classified_executor_function
fn[T : ExecutorCode] make_classified_executor_function(name : String?, params : Array[String], closure : Environment, strict : Bool, code : T, source_body : Array[Stmt], rest_param? : String?, constructable? : Bool, call_self_name? : Bool, define_arguments_object? : Bool) -> ValueExecutorCode providers are trusted to supply code corresponding to
source_body; runtime admission cannot prove otherwise.
make_executor_arrow_function
fn[T : ExecutorCode] make_executor_arrow_function(params : Array[String], closure : Environment, strict : Bool, code : T, rest_param? : String?) -> Valuemake_executor_function
fn[T : ExecutorCode] make_executor_function(name : String?, params : Array[String], closure : Environment, strict : Bool, code : T, rest_param? : String?, constructable? : Bool, call_self_name? : Bool, define_arguments_object? : Bool) -> Valuemake_host_object
Create a host object with methods, accessors, intent-shaped data properties,
and embedder host slots (#517). Returns Value so callers need not match
on ObjectData. Composes install_builtin_* and set_host_slot.
Parameters
- name — [[Class]] / class_name string (e.g. "Element").
- proto — [[Prototype]]. Defaults to Null (not %Object.prototype%); pass a realm object prototype when the host object should inherit from it.
- methods — string-keyed callables with builtin method descriptors.
- accessors — map of name → (getter?, setter?). At least one side must be Some; use None for an absent side.
- non_writable / frozen — rare constant data props (builtin descriptors).
- host_slots — embedder-private state keyed by pre-reserved HostSlotKey values (HostSlotKey::reserve() once per slot kind, then build the map).
- extensible — [[Extensible]] (default true).
Install order: non_writable → frozen → methods → accessors →
host_slots. Same string key across the JS maps: later step wins (factory
stomping, not [[DefineOwnProperty]] — avoid dual-defining the same name,
including overwriting a frozen key).
make_interp_method_func
fn make_interp_method_func(name~ : String, length? : Int, realm_state? : RealmState?, func : (Interpreter, Value, Array[Value]) -> Value raise) -> ValueInterpreter-aware method function: callback receives interpreter and this.
Signature (Interpreter, Value, Array[Value]) -> Value raise Error.
make_interp_method_func_with_context
fn make_interp_method_func_with_context(name~ : String, length? : Int, func : (Interpreter, CallContext, Value, Array[Value]) -> Value raise) -> ValueInterpreter-aware method function with explicit call/construct context.
make_interp_static_func
fn make_interp_static_func(name~ : String, length? : Int, func : (Interpreter, Array[Value]) -> Value raise) -> ValueInterpreter-aware static function: callback receives interpreter but not this.
Signature (Interpreter, Array[Value]) -> Value raise Error.
make_materialized_tree_function
fn make_materialized_tree_function(request : FunctionMaterializationRequest, child_materializer : FunctionMaterializer?) -> Valuemake_method_func
Method function: callback receives this. Signature
(Value, Array[Value]) -> Value raise Error.
make_native_func
fn make_native_func(name~ : String, length? : Int, realm_state? : RealmState?, func : (Array[Value]) -> Value raise) -> ValueNon-constructable native function: callback is (Array[Value]) -> Value raise Error.
Use for built-in free functions and static methods.
make_object
Helper to create a basic object with default empty symbol maps
make_prepared_executor_arrow_function
fn[T : ExecutorCode] make_prepared_executor_arrow_function(params : Array[String], closure : Environment, strict : Bool, code : T, activation_capability_summary : ExecutorActivationCapabilitySummary?, source_text? : String?, rest_param? : String?) -> Valuemake_prepared_executor_function
fn[T : ExecutorCode] make_prepared_executor_function(name : String?, params : Array[String], closure : Environment, strict : Bool, code : T, activation_capability_summary : ExecutorActivationCapabilitySummary?, source_text? : String?, rest_param? : String?, constructable? : Bool, call_self_name? : Bool, define_arguments_object? : Bool, needs_own_environment? : Bool) -> Valuemake_tagged_template_object
mark_as_method
Mark a function value as a method-shorthand definition ({ m() {} }).
Per ES §15.4.5 MethodDefinitionEvaluation, such functions have no
[[Construct]] internal method and must throw TypeError when called via
new. Sets is_method: true on the FuncData/FuncDataExt.
Non-UserFunc/UserFuncExt values (generators, async functions, etc.)
pass through unchanged — they have their own non-constructor semantics.
module_namespace_set_prototype_result
Module-namespace exotic object [[SetPrototypeOf]] shortcut (§28.3 /
§10.4.6.2). Relocated from interpreter/stdlib/module_namespace_helpers.mbt;
the stdlib_ name prefix is dropped because runtime is now the defining
package (necessary move fixup, not a redesign). Shared by
Reflect.setPrototypeOf and Object.setPrototypeOf.
new_promise_data
Create a new pending promise data structure
object_get_prototype_of
object_is_extensible
O.[[IsExtensible]]() backing for Object.isExtensible (§20.1.2.12).
object_prevent_extensions
O.[[PreventExtensions]]() backing for Object.preventExtensions
(§20.1.2.17). A falsy Proxy trap result is an exceptional completion here.
object_set_prototype_of
target.[[SetPrototypeOf]](proto) backing for Reflect.setPrototypeOf
(§28.1.13). Argument-count validation stays at the stdlib boundary; this op
performs the proto-type validation and the match target dispatch verbatim,
including the non-object TypeError arm and the Reflect-specific "return false"
(rather than throw) on a non-extensible target.
observe_source_failure
fn[T] observe_source_failure(realm_state : RealmState, eval : () -> T raise) -> Result[T, SourceObservedFailure]Observe source provenance atomically without changing the raised error.
Nested call wrappers record an error only while this scope is active.
ordinary_get_own_property
ES §10.1.5 OrdinaryGetOwnProperty(O, P). Returns the stored descriptor
for an own property on val. For Array, synthesizes descriptors for
length and in-range indexed elements per §10.4.2. Returns None if the
property is not own.
ordinary_get_own_value_for_descriptor
Extract the stored own value for key on val. Mirrors the key-aware
reader used in proxy helpers but surfaced here for VAP's value-change
check (step 4.b.iii).
ordinary_set_prototype
[[SetPrototypeOf]] cycle detection and extensibility guard for ordinary objects
(§10.1.2.1). Returns true if the prototype was set, false if it would create a
cycle or the target is non-extensible. Does NOT handle immutable-prototype
exotic objects (Object.prototype) — callers check before reaching this.
own_string_property_names
Object.getOwnPropertyNames (§20.1.2.11): the String-typed own keys from the
canonical [[OwnPropertyKeys]] enumeration. Array holes and TypedArray
validity are handled by the canonical op.
own_symbol_properties
Object.getOwnPropertySymbols (§20.1.2.12): the Symbol-typed own keys from the
canonical [[OwnPropertyKeys]] enumeration.
plan_numeric_update
prepare_compiled_script_early_error
fn prepare_compiled_script_early_error(stmts : Array[Stmt], strict : Bool, provenance_token? : Ref[Unit]?) -> CompiledScriptEarlyErrorSettlementprepare_executor_activation_capability
fn prepare_executor_activation_capability(params : Array[String], body : Array[Stmt]) -> ExecutorActivationCapabilitySummary?proxy_define_property
fn proxy_define_property(interp : Interpreter, proxy_data : ProxyData, key : Value, partial : PartialDescriptor) -> Bool raiseES §10.5.6 [[DefineOwnProperty]] (Proxy). Invokes the defineProperty
trap and validates:
- trap returns falsy -> return false
- trap returns true + target has no own desc + target non-extensible -> TypeError
- trap returns true + incoming descriptor is non-configurable + target descriptor doesn't exist / is configurable -> TypeError
- trap returns true + existing target desc non-configurable incompatible with incoming -> TypeError
proxy_delete_property
Implement the Proxy [[Delete]] invariant checks per ES §10.5.10.
proxy_get
fn proxy_get(interp : Interpreter, proxy_data : ProxyData, key : String, receiver : Value) -> Value raiseString-key compatibility wrapper for existing [[Get]] call sites.
proxy_get_own_property
fn proxy_get_own_property(interp : Interpreter, proxy_data : ProxyData, key : Value) -> (PropDescriptor, Value)? raiseES §10.5.5 [[GetOwnProperty]] (Proxy). Invokes the
getOwnPropertyDescriptor trap with the canonical invariant set:
- trap returns non-object non-undefined -> TypeError
- target's own desc is non-configurable AND trap returns undefined -> TypeError
- target is non-extensible + no own desc + trap returns object -> TypeError
- trap reports non-configurable + non-writable; target is NOT both -> TypeError
- target non-configurable accessor: getter/setter identity must match (SameValue) Returns the completed descriptor or None.
proxy_get_prototype_of
Implement the Proxy [[GetPrototypeOf]] internal method per ES §10.5.1.
proxy_has_property
Implement the Proxy [[HasProperty]] invariant checks per ES §10.5.7.
Called after the has trap returns a result.
proxy_has_property_key
proxy_is_extensible
Implement the Proxy [[IsExtensible]] internal method per ES §10.5.3.
proxy_own_property_keys
Implement the Proxy [[OwnPropertyKeys]] internal method per ES §10.5.11.
Calls the ownKeys trap, validates the result against the target's invariants,
and returns the validated list of keys as an Array value.
proxy_prevent_extensions
Implement the Proxy [[PreventExtensions]] internal method per ES §10.5.4.
proxy_set
fn proxy_set(interp : Interpreter, proxy_data : ProxyData, key : String, value : Value, receiver : Value, strict : Bool) -> Value raiseImplement the Proxy [[Set]] invariant checks per ES §10.5.9.
proxy_set_prototype_of
fn proxy_set_prototype_of(interp : Interpreter, proxy_data : ProxyData, proto : Value) -> Bool raiseImplement the Proxy [[SetPrototypeOf]] internal method per ES §10.5.2.
raise_js_exception
Raise a JavaScript exception with the given value.
This is the only way for external packages to raise JsException since
suberror constructors from other packages are read-only in MoonBit.
realm_value_to_json
Copy a runtime value into strict JSON data without performing property
lookup, calling getters or toJSON, or consulting a mutable global.
reflect_get_with_receiver
target receiver-aware [[Get]] backing for Reflect.get (§28.1.7). Argument
validation and the non-object TypeError check stay at the stdlib boundary;
this op performs the receiver-aware descriptor walk verbatim. The former
try_get_with_receiver closure's captures are threaded as parameters; its
body is unchanged.
reject_promise
Reject a promise with the given reason.
Triggers all reject reactions as microtasks.
revoke_proxy
Revoke a proxy by nullifying its target and handler slots. The cached
The cached call/construct classifications are intentionally left untouched:
revocation clears the target and handler slots, not the Proxy's internal
[[Call]] and [[Construct]] methods.
set_array_iterator_override
fn set_array_iterator_override(arr : ArrayData, well_known_symbols~ : WellKnownSymbols, getter : Value?, value : Value?) -> Unitset_array_length_override
Store sparse Array length state in the ArrayData PropertyBag. This keeps
Array exotic state attached to the array object instead of a module-level
identity side table, using a non-forgeable internal symbol id so ordinary
string-keyed property lookup cannot observe it.
set_array_like_element
Set indexed element on array-like value
set_array_like_length
Set the length property on an array-like value
set_array_named_prop
set_array_prototype_override
set_array_symbol_prop
set_function_name
SetFunctionName: set name property on anonymous functions per ES2015+.
Only sets name if the current name is empty (anonymous).
set_integrity_frozen
SetIntegrityLevel(O, frozen) backing for Object.freeze (§20.1.2.6).
set_integrity_sealed
SetIntegrityLevel(O, sealed) backing for Object.seal (§20.1.2.20).
set_keyed_collection_iterator_next_index
set_private_field
Write a private field value on an object.
Raises TypeError if brand check fails.
setup_async_function_constructor
fn setup_async_function_constructor(env : Environment, well_known_symbols~ : WellKnownSymbols) -> UnitSet up the AsyncFunction constructor and prototype chain.
Mirrors setup_generator_function_constructor in generator.mbt.
Prototype chain (per ES spec):
AsyncFunction.proto === Function
AsyncFunction.prototype.proto === Function.prototype
AsyncFunction.prototype[@@toStringTag] === "AsyncFunction"
AsyncFunction.prototype.constructor === AsyncFunction
setup_async_generator_function_constructor
fn setup_async_generator_function_constructor(env : Environment, well_known_symbols~ : WellKnownSymbols) -> UnitSet up the AsyncGeneratorFunction constructor and prototype chain.
Mirrors setup_generator_function_constructor in generator.mbt.
Prototype chain (per ES spec §27.4):
%AsyncGeneratorFunction%.proto === Function
%AsyncGeneratorFunction%.prototype.proto === Function.prototype
%AsyncGeneratorFunction%.prototype[@@toStringTag] === "AsyncGeneratorFunction"
%AsyncGeneratorFunction%.prototype.constructor === %AsyncGeneratorFunction%
%AsyncGeneratorFunction%.prototype.prototype === %AsyncGeneratorPrototype%
%AsyncIteratorPrototype%.proto === Object.prototype
%AsyncIteratorPrototype%[@@asyncIterator] returns this
%AsyncGeneratorPrototype%.proto === %AsyncIteratorPrototype%
%AsyncGeneratorPrototype%.constructor === %AsyncGeneratorFunction%.prototype
%AsyncGeneratorPrototype%[@@toStringTag] === "AsyncGenerator"
setup_generator_function_constructor
fn setup_generator_function_constructor(env : Environment, global_this : Value, well_known_symbols~ : WellKnownSymbols) -> UnitSet up the GeneratorFunction constructor on the given interpreter.
GeneratorFunction("a", "yield a") creates a generator function,
analogous to Function("a", "return a") for regular functions.
sort_property_keys
Sort property keys per OrdinaryOwnPropertyKeys spec order:
- Integer indices in ascending numeric order
- Other string keys in insertion order
stamp_function_realm
stamp_function_realm_with
string_to_utf16
Convert a MoonBit string (sequence of Unicode code points) to an array
of UTF-16 code units. Supplementary characters (code point > 0xFFFF) are
split into a surrogate pair (high surrogate + low surrogate).
strip_self_name_binding
Rebuild a function value with has_name_binding: false on its
FuncData/FuncDataExt. Used for method-shorthand definitions (in
object literals) where the parser emits FuncExpr/FuncExprExt with
name = Some(key) for fn.name purposes, but §15.2.5's self-name
binding does NOT apply. Non-UserFunc/UserFuncExt values pass
through unchanged (nothing to strip).
test_integrity_frozen
TestIntegrityLevel(O, frozen) backing for Object.isFrozen (§20.1.2.13).
test_integrity_sealed
TestIntegrityLevel(O, sealed) backing for Object.isSealed (§20.1.2.15).
to_array_like_elements
Convert array-like value to an Array of Values
to_array_like_length
ToLength: Get length from any value as per ECMAScript spec (array-like objects)
to_array_like_length_interp
ToLength with full interpreter support for user-defined getter-based length
to_index
ECMAScript ToIndex: converts a value to a non-negative integer index.
Throws RangeError for negative values or values >= 2^53.
Returns 0 for undefined.
to_js_string
ECMAScript ToString - converts a value to a string following the spec.
For objects, calls ToPrimitive(hint: "string") then converts result to string.
to_primitive_default
ToPrimitive(input, hint "default") - for + operator.
Same as "number" except passes "default" to @@toPrimitive.
to_primitive_number
ToPrimitive(input, hint "number") - converts an object to a primitive value.
Follows the ECMAScript spec: check @@toPrimitive, then valueOf, then toString.
to_property_key
ECMAScript ToPropertyKey §7.1.19 — canonicalize a Value into a property
key. Symbols pass through; anything else is ToPrimitive(hint:"string") +
ToString via to_js_string, which invokes user-land Symbol.toPrimitive
/ toString hooks (so the caller observes side-effects in spec order).
unwrap_grouping
Strip consecutive Grouping nodes from an expression.
Per ES spec, grouping parentheses do not change the Reference type,
so ((eval))("code") is still a direct eval call.
utf16_length
fn utf16_length(s : String) -> IntGet the UTF-16 length of a string (counting code units, not code points).
validate_compiled_script_early_errors
validate_function_constructor_params
Apply parameter-list early errors for functions built via the
Function / GeneratorFunction / AsyncFunction / AsyncGeneratorFunction
constructors. Per spec these fire at construction time, not at call.
Three checks:
- Non-simple parameter list with "use strict" directive in body is a SyntaxError (§15.1.1 / §14.1.2).
- Strict-mode (or non-simple) parameter list must not contain duplicate names.
- Strict-mode parameter names must not be eval, arguments, or a strict-reserved word (§15.1.5).
validate_function_constructor_params_ext
validate_function_signature
validate_function_signature_ext
validate_non_configurable
fn validate_non_configurable(existing : PropDescriptor, prop_display : String, is_accessor : Bool, is_data : Bool, has_value : Bool, new_writable : Bool?, new_enumerable : Bool?, new_configurable : Bool?, new_getter : Value?, new_setter : Value?, get_old_value : () -> Value, get_new_value : () -> Value?) -> Unit raiseValidate non-configurable property constraints per ES spec [[DefineOwnProperty]].
Throws TypeError if the proposed descriptor change violates invariants.
This is the sole authority for descriptor mutation constraints in the runtime.
verify_executor_activation_capability
fn verify_executor_activation_capability(params : Array[String], body : Array[Stmt], summary : ExecutorActivationCapabilitySummary?) -> Boolwith_active_realm_state_unit
with_source_identity
fn[T] with_source_identity(realm_state : RealmState, source_identity : String?, eval : () -> T raise) -> T raiseSource Files
- activation_dispatch_admission.mbt
- activation_dispatch_changing_receiver.mbt
- activation_dispatch_composition.mbt
- activation_dispatch_constructor_admission.mbt
- activation_dispatch_constructor_trust.mbt
- activation_dispatch_control_admission.mbt
- activation_dispatch_core.mbt
- activation_dispatch_direct_call_admission.mbt
- activation_dispatch_direct_call_trust.mbt
- activation_dispatch_direct_return_admission.mbt
- activation_dispatch_direct_return_trust.mbt
- activation_dispatch_getter_admission.mbt
- activation_dispatch_getter_trust.mbt
- activation_dispatch_map_admission.mbt
- activation_dispatch_map_core.mbt
- activation_dispatch_map_shell.mbt
- activation_dispatch_mutual_receiver_admission.mbt
- activation_dispatch_mutual_receiver_trust.mbt
- activation_dispatch_numeric_expression.mbt
- activation_dispatch_property.mbt
- activation_dispatch_proxy_admission.mbt
- activation_dispatch_proxy_trust.mbt
- activation_dispatch_receiver_admission.mbt
- activation_dispatch_receiver_ownership.mbt
- activation_dispatch_receiver_trust.mbt
- activation_dispatch_result_pipeline.mbt
- activation_dispatch_root_admission.mbt
- activation_dispatch_shell.mbt
- activation_dispatch_trust.mbt
- activation_observation.mbt
- array_like.mbt
- async.mbt
- binding_reference.mbt
- builtin_install.mbt
- call.mbt
- callback_free_binding.mbt
- canonical_proxy_constructor.mbt
- class.mbt
- compiled_script.mbt
- compiled_script_preparation.mbt
- construct.mbt
- conversions.mbt
- destructuring.mbt
- destructuring_plan.mbt
- enumerable_own_properties.mbt
- environment.mbt
- errors.mbt
- eval_comma.mbt
- eval_contains.mbt
- eval_expr.mbt
- exec_stmt.mbt
- execution_control.mbt
- execution_policy.mbt
- executor_activation.mbt
- executor_activation_capability.mbt
- executor_array_for_each.mbt
- executor_binding.mbt
- executor_coercing_addition.mbt
- executor_coercing_multiplicative.mbt
- executor_coercing_relational.mbt
- executor_coercing_subtraction.mbt
- executor_copy_data_properties.mbt
- executor_iterable_spread.mbt
- executor_numeric_conversion.mbt
- executor_property_delete.mbt
- factories.mbt
- function_materializer.mbt
- generator.mbt
- hoisting.mbt
- host_slots.mbt
- integrity_ops.mbt
- internal_slots.mbt
- interpreter.mbt
- intrinsic_promise.mbt
- iterator_protocol.mbt
- iterators.mbt
- json_bridge.mbt
- microtask_policy.mbt
- module_default_export.mbt
- module_graph.mbt
- module_namespace.mbt
- modules.mbt
- numeric_update_plan.mbt
- operators.mbt
- own_property_keys.mbt
- promise_core.mbt
- promise_executor.mbt
- property.mbt
- property_own.mbt
- property_set.mbt
- prototype_ops.mbt
- proxy_helpers.mbt
- realm_state.mbt
- reflect_value_ops.mbt
- stdlib_hooks.mbt
- string_utils.mbt
- symbols.mbt
- timer_policy.mbt
- tree_executor_frame.mbt
- value.mbt
Install
Download zipPure MoonBit cross-target embedded JavaScript engine
javascriptinterpreterembeddedscripting
0.9.0
Apache-2.0
Updated 4 hours ago
3K downloadsDependencies
- moonbitlang/x0.5.1
- moonbitlang/async0.21.0
- moonbit-community/normalization0.5.0