Hooks

not-empty.ts

export default function<TValue>(
  value: TValue | null | undefined
): value is TValue {
  return value !== null && value !== undefined
}

use-refreshable-promise.ts

import { useMemo } from 'react'
import { usePromise } from 'react-hook-utils'

export default <T>(
  fetchResult: () => Promise<T>,
  setResult: (result: T) => any
) => {
  const fetchAndStore = async () => {
    return fetchResult().then((result) => {
      setResult(result)
    })
  }
  const fetchMemo = useMemo(fetchAndStore, [])
  const [, error, isLoading] = usePromise(fetchMemo)

  return {
    isLoading,
    error,
    refresh: fetchAndStore
  }
}

use-set-timeout.ts

import { useEffect } from 'react'

export default (fn: () => void, delay: number, bind?: any[]) => {
  useEffect(() => {
    if (delay === 0) {
      fn()
      return
    }

    const timer = window.setTimeout(fn, delay)
    return () => {
      window.clearTimeout(timer)
    }
  }, bind || [])
}