Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Fixed example in addon.md. #820

Merged
merged 3 commits into from
Oct 13, 2020
Merged

Fixed example in addon.md. #820

Changes from 2 commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
f0a89db
Fixed example in addon.md.
nempoBu4 Oct 8, 2020
1fcf880
Added env to Napi::Object::New
nempoBu4 Oct 8, 2020
aa2107a
Put back napi_enumerable
nempoBu4 Oct 10, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
6 changes: 3 additions & 3 deletions doc/addon.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -41,9 +41,9 @@ class ExampleAddon : public Napi::Addon<ExampleAddon> {

// We can also attach plain objects to `exports`, and instance methods as
// properties of those sub-objects.
InstanceValue("subObject", DefineProperties(Napi::Object::New(), {
InstanceMethod("decrement", &ExampleAddon::Decrement
})), napi_enumerable)
InstanceValue("subObject", DefineProperties(Napi::Object::New(env), {
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I understand adding the env to New() but not removing napi_enumerable as the signature seems like it requires that:

node-addon-api/napi-inl.h

Line 3425 in ceb27d4

inline ClassPropertyDescriptor<T> InstanceWrap<T>::InstanceValue(

Copy link
Contributor Author

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

According to InstanceWrap doc:

template <typename T>
static Napi::ClassPropertyDescriptor<T>
Napi::InstanceWrap<T>::InstanceValue(const char* utf8name,
                            Napi::Value value,
                            napi_property_attributes attributes = napi_default);

napi_enumerable can be set but it is not required. I have verified that this code works.

But if you think that napi_enumerable needs to be included into this example then it still needs to be fixed because of wrong position of brackets:

InstanceValue("subObject", DefineProperties(Napi::Object::New(env), {
    InstanceMethod("decrement", &ExampleAddon::Decrement) // <- missing bracket
})/*) <- wrong bracket */, napi_enumerable)

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Without napi_enumerable the items cannot be seen from JS without some effort. Please leave it in place! Everything else LGTM.

Copy link
Contributor Author

@nempoBu4 nempoBu4 Oct 10, 2020 •
edited
Loading

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

@gabrielschulhof I thought napi_enumerable means this items can be seen through for..in iteration or Object.keys as stated in the MDN's Enumerability and ownership of properties article. I thought without napi_enumerable the property still can be accessed through dot (obj.property) or brackets (obj['property']) or destructuring assignment ({ property } = obj) and there is no harm to remove napi_enumerable because there is no for..in iteration in addon.md.

So, I was wrong. I put napi_enumerable back in place. Does it mean that napi_enumerable needs to be added to other items too?

DefineAddon(exports, {
  InstanceMethod("increment", &ExampleAddon::Increment, napi_enumerable), // <- here

  // We can also attach plain objects to `exports`, and instance methods as
  // properties of those sub-objects.
  InstanceValue("subObject", DefineProperties(Napi::Object::New(env), {
    InstanceMethod("decrement", &ExampleAddon::Decrement, napi_enumerable) // <- and here
  }), napi_enumerable)
});

InstanceMethod("decrement", &ExampleAddon::Decrement)
}))
});
}
private:
Expand Down