destructuring for class fields

💡 Ideas
1

I would love to destructor onto class fields. For example:

function foo() {
  return [1, 2]
}

class MyClass {
  ;[one, two] = foo()
}

const o = new MyClass()

o.one // 1
o.two // 2

And similar with object destructuring.

This could go well with constructor args available in fields: Proposal: access to constructor parameters in field initializers

Real-world use case:

Solid.js, for example, provides a createSignal function that returns a tuple:

  • a function for reading a value (a "getter")
  • a function for setting a value (a "setter")
const [foo, setFoo] = createSignal(0)

// increment the value every second:
setInterval(() => setFoo(foo() + 1))

// log the value every second:
createEffect(() => console.log(foo()))

With destructuring we could easily do this:

class MyClass {
  ;[foo, setFoo] = createSignal(0)
}

const o = new MyClass

o.foo() // read
o.setFoo(123) // write

This is expecially nice in lieu of decorators which will allow us to make reactive properties easily. Plus some people prefer less magic, and assigning a getter and setter from createSignal to two properties is less to explain than a decorator may be.

Plus not everything is about reactivity, there might just be something that returns a tuple of distince things, or an object:

class MyClass {
  ;{value, abort, interval} = someProcess() // syntax? 
}
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