[Feature]: Will Fabric v6 support user-defined Object properties?

[wangrongding]

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• I am filing a FEATURE request.

Description

Will Fabric v6 support user-defined Object properties?

For example, when I want to create an element, I can embed an Id in the object for convenient future use. Currently, Fabric v5 does not support this due to ts type restrictions, so I am currently using Object.assign to merge the ID with the target object.

Current State

Additional Context

No response

[asturur]

fabric v6 sort of supports that but the definition of types are hard to do.
This should definitely be explained in some doc.

[ouyoungs]

mean this?
https://juejin.cn/post/7153068432303325220

let canvas = new Canvas('c')

let rect = new Rect({
  width: 30,
  height: 30,
  top: 10,
  left: 10,
  my_id: 'rect01'
})

canvas.add(rect)

function handleToJSON() {
  console.log(canvas.toJSON(['my_id']))
}

[wangrongding]

I know this, I'm talking about the official api and support for Typescript type.

[asturur]

i think today you can do:

const newText = new FabricText<{ id: string } & Partial<TextProps>>('myText', {
  id: 'hello',
  fontFamily: 'Arial',
});

But i m sure there will be some kind of hiccups here and there, is not as smooth as we want, is also hard to do because of mixins and everything.

Slowly mixin will go away and hopefully will be simple