Function findKey

underscore.js:1267–1274

(obj, predicate, context)

  // Returns the first key on an object that passes a truth test.
  function findKey(obj, predicate, context) {
    predicate = cb(predicate, context);
    var _keys = keys(obj), key;
    for (var i = 0, length = _keys.length; i < length; i++) {
      key = _keys[i];
      if (predicate(obj[key], key, obj)) return key;
    }
  }

  // Internal function to generate `_.findIndex` and `_.findLastIndex`.
  function createPredicateIndexFinder(dir) {