Provide convenience type InterpreterFrom<typeof machine>

[VanTanev]

Add the convenience type

export type InterpreterFrom<
  T extends StateMachine<any, any, any, any>
> = T extends StateMachine<
  infer TContext,
  infer TStateSchema,
  infer TEvent,
  infer TTypestate
>
  ? Interpreter<TContext, TStateSchema, TEvent, TTypestate>
  : never;

This is useful in the following pattern:

import React from 'react'
import { createMachine, InterpreterFrom } from 'xstate'
import { useService } from '@xstate/react'

const machine = createMachine(...)
type MachineService = InterpreterFrom<typeof machine>

const MachineServiceContext = React.createContext<MachineService>(null!)
const useMachineService = (): MachineService  => {
  const service = React.useContext(MachineServiceContext)
  if (!service) throw new Error(`You must call useMachineService in a child component of <MachineProvider>`)
  return service
}
const MachineProvider: React.FC = ({ children }) => {
  const service = useInterpret(machine)
  return <MachineServiceContext.Provider value={service}>{children}</MachineServiceContext.Provider>
}

const App = () => {
  return <MachineProvider><Compontent /></MachineProvider>
}
const Component = () => {
  const service = useMachineService()
  const [state, send] = useService(service)
  // ...
}

This is a companion type to ActorRefFrom<T>.

[changeset-bot]

🦋 Changeset detected

Latest commit: 25d93b5

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
xstate	Patch

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