Svelte media-query readable stores

mq.js

const setupMQ = (queryString) => (set) => {
  const query = window.matchMedia(queryString)
  const callback = (e) => set(e.matches)
  query.addListener(callback)
  callback(query)
  return (query) => query.removeListener(callback)
}

// example use

import { readable } from 'svelte/store'

export const isDesktop = readable(false, setupMQ('screen and (min-width: 769px)'))