[Javascript] Broadcaster + Operator + Listener pattern -- 27. combine multi broadcaster and compose operator to implement game logic

New broadcaster: compose:

export let combine = (broadcaster1, broadcaster2) => listener => {
  let value1;
  let value2;

  let cancel1 = broadcaster1(value => {
    value1 = value;
    listener([
      value1,
      value2
    ])
  })

  let cancel2 = broadcaster2(value => {
    value2 = value;
    listener([
      value1,
      value2
    ])
  })

  return () => {
    cancel1();
    cancel2();
  }
}

Game logic:

import React from "react"
import { render } from "react-dom"

import {
  useBroadcaster,
  getUrl,
  useListener,
  combine,
} from "./broadcasters"
import { map, share, targetValue, filter} from "./operators"
import {pipe, every, isString} from "lodash/fp"
import { head  } from "lodash"

let getWord = pipe(
    map(head),
    share()
  )(getUrl('https://random-word-api.herokuapp.com/word'))

// gameLgoic take broadcaster will receive values: [guess, word]
let gameLogic = pipe(
  filter(every(isString)),
  map(([guess, word]) => {
    return Array.from(word).map(c => guess.includes(c) ? c: "*").join("")
  })
)

let App = () => {
  let onInput = useListener();
  let gameBroadcaster = gameLogic(combine(targetValue(onInput), getWord))
  let word = useBroadcaster(getWord)
  let game = useBroadcaster(gameBroadcaster, "")
  return (
    <div>
      <input type="text" onInput={onInput} />
      <p>
        {word}
      </p>
      <p>{game}</p>
    </div>
  )
}

render(<App></App>, document.querySelector("#root"))