JS values passed improperly to Lua callbacks

[s-ol]

This works fine:

local canvas = document:createElement('canvas')
canvas.width = 400
canvas.height = 400
function canvas:onclick(event)
  print(event.offsetX, event.offsetY)
end

document.body:appendChild(canvas)

but this prints nil for the values in event:

local canvas = document:createElement('canvas')
canvas.width = 400
canvas.height = 400
canvas:addEventListener('click', function (event)
  print(event.offsetX, event.offsetY)
end)

document.body:appendChild(canvas)

the event is passed correctly, as it's printed as [object HTMLCanvasEvent].

The same restriction prevents me from accessing for example the timestamp passed into a requestAnimationFrame callback.

Given that I know the type of the JS object there, isn't there a way I can at least extract the properties?

[daurnimator]

The first argument to your callback is this. The second argument is the event object.

[s-ol]

welp, you're right 😄
I could swear I was printing the number but couldn't use it in the second case but seems like this is on me...

Going to close this, but while I'm here: is there a way I can extend an ES6 class defined in JS with Lua?

[daurnimator]

You can do it manually, but a helper might be nice. That's tracked in #29