Struct v8::PropertyCallbackArguments

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pub struct PropertyCallbackArguments<'s>(_);

Implementations§

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impl<'s> PropertyCallbackArguments<'s>

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pub fn holder(&self) -> Local<'s, Object>

Returns he object in the prototype chain of the receiver that has the interceptor. Suppose you have x and its prototype is y, and y has an interceptor. Then info.this() is x and info.holder() is y. The holder() could be a hidden object (the global object, rather than the global proxy).

For security reasons, do not pass the object back into the runtime.

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pub fn this(&self) -> Local<'s, Object>

Returns the receiver. In many cases, this is the object on which the property access was intercepted. When using Reflect.get, Function.prototype.call, or similar functions, it is the object passed in as receiver or thisArg.

  void GetterCallback(Local<Name> name,
                      const v8::PropertyCallbackInfo<v8::Value>& info) {
     auto context = info.GetIsolate()->GetCurrentContext();

     v8::Local<v8::Value> a_this =
         info.This()
             ->GetRealNamedProperty(context, v8_str("a"))
             .ToLocalChecked();
     v8::Local<v8::Value> a_holder =
         info.Holder()
             ->GetRealNamedProperty(context, v8_str("a"))
             .ToLocalChecked();

    CHECK(v8_str("r")->Equals(context, a_this).FromJust());
    CHECK(v8_str("obj")->Equals(context, a_holder).FromJust());

    info.GetReturnValue().Set(name);
  }

  v8::Local<v8::FunctionTemplate> templ =
  v8::FunctionTemplate::New(isolate);
  templ->InstanceTemplate()->SetHandler(
      v8::NamedPropertyHandlerConfiguration(GetterCallback));
  LocalContext env;
  env->Global()
      ->Set(env.local(), v8_str("obj"), templ->GetFunction(env.local())
                                           .ToLocalChecked()
                                           ->NewInstance(env.local())
                                           .ToLocalChecked())
      .FromJust();

  CompileRun("obj.a = 'obj'; var r = {a: 'r'}; Reflect.get(obj, 'x', r)");

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