Function DerivedCell

DerivedCell<T>(
    value: T,
    linkFn: (r: Realm, cell: NodeRef<T>) => NodeRef<T>,
    distinct?: Distinct<T>,
): NodeRef<T>
Defines a new stateful node, links it to an existing node transform and returns a reference to it. Once a realm instance publishes or subscribes to the node, an instance of that node it will be registered in the realm.
Type Parameters
- T
Parameters
- value: T
  the initial value of the node. Stateful nodes always have a value.
- linkFn: (r: Realm, cell: NodeRef<T>) => NodeRef<T>
  an function that will be called when the node is registered in a realm. Should return a node reference to link to.
- distinct: Distinct<T> = true
  if true, the node will only emit values that are different from the previous value. Optionally, a custom distinct function can be provided if the node values are non-primitive.
Returns NodeRef<T>
Example
```
const bar$ = Cell('bar')
const foo$ = DerivedCell('foo',  (r, cell$) => {
r.sub(cell$, console.log)
return r.pipe(bar$, (bar) => `foo${bar}`)
}, true)
const r = new Realm()
r.pub(bar$, '-bar') // the subscription will log 'bar'
```
- Defined in realm.ts:1293