index.js
function clonePureArray (subject, host) {
  var i = subject.length
  var start = host.length

  while (i --) {
    host[start + i] = subject[i]
  }

  return host
}
function clonePureArray (subject, host) {
  var i = subject.length
  var start = host.length

  while (i --) {
    host[start + i] = subject[i]
  }

  return host
}
function clonePureArray ( subject , host ) { var i = subject . length var start = host . length while ( i -- ) { host [ start + i ] = subject [ i ] } return host }
clone an object as a pure subject, and ignore non-number properties
@param {Array} subject
@param {Array|Object} host required, receiver which the subject be cloned to
clone an object as a pure subject and ignore non - number properties