is-implemented.js 469 B

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  1. "use strict";
  2. module.exports = function () {
  3. var arr = [1, "foo"], iterator, result;
  4. if (typeof arr.entries !== "function") return false;
  5. iterator = arr.entries();
  6. if (!iterator) return false;
  7. if (typeof iterator.next !== "function") return false;
  8. result = iterator.next();
  9. if (!result || !result.value) return false;
  10. if (result.value[0] !== 0) return false;
  11. if (result.value[1] !== 1) return false;
  12. if (result.done !== false) return false;
  13. return true;
  14. };