How to use the ssb-ref.isHash function in ssb-ref

'use strict';

var isRef = require('ssb-ref')
var isHash = isRef.isHash
var isFeedId = isRef.isFeedId
var contpara = require('cont').para
var explain = require('explain-error')
// make a validation stream?
// read the latest record in the database
// check it against the incoming data,
// and then read through

function clone (obj) {
  var o = {}
  for(var k in obj) o[k] = obj[k];
  return o
}

function get (db, key) {
  return function (cb) {

var ref = require('ssb-ref')
var ssbKeys = require('ssb-keys')
var isHash = ref.isHash
var isFeedId = ref.isFeedId
var timestamp = require('monotonic-timestamp')
var isCanonicalBase64 = require('is-canonical-base64')
var isEncryptedRx = isCanonicalBase64('','\.box.*')
var isSignatureRx = isCanonicalBase64('','\.sig.\w+')

function isValidOrder (msg, signed) {
  var i = 0
  var keys = Object.keys(msg)
  if(signed && keys.length !== 7) return false
  if(
    keys[0] !== 'previous' ||
    keys[3] !== 'timestamp' ||
    keys[4] !== 'hash' ||
    keys[5] !== 'content' ||
    (signed && keys[6] !== 'signature')

'use strict'
var ssbKeys = require('ssb-keys')
var timestamp = require('monotonic-timestamp')
var isRef = require('ssb-ref')
var isHash = isRef.isHash
var isFeedId = isRef.isFeedId

var encode = exports.encode = function (obj) {
  return JSON.stringify(obj, null, 2)
}

function isString (s) {
  return 'string' === typeof s
}

function isInteger (n) {
  return ~~n === n
}

function isObject (o) {
  return o && 'object' === typeof o