Function getIterator

lib/web/polyfill.js:546–551

(it)

  return hasExt || SYMBOL_ITERATOR in O || has(Iterators, classof(O));
}
function getIterator(it){
  var Symbol  = global[SYMBOL]
    , ext     = it[Symbol && Symbol[ITERATOR] || FF_ITERATOR]
    , getIter = ext || it[SYMBOL_ITERATOR] || Iterators[classof(it)];
  return assertObject(getIter.call(it));
}
function stepCall(fn, value, entries){
  return entries ? invoke(fn, value) : fn(value);
}