core-js/modules/es.iterator.find.js

Standard library

'use strict';
var $ = require('../internals/export');
var call = require('../internals/function-call');
var iterate = require('../internals/iterate');
var aCallable = require('../internals/a-callable');
var anObject = require('../internals/an-object');
var getIteratorDirect = require('../internals/get-iterator-direct');
var iteratorClose = require('../internals/iterator-close');
var iteratorHelperWithoutClosingOnEarlyError = require('../internals/iterator-helper-without-closing-on-early-error');

var findWithoutClosingOnEarlyError = iteratorHelperWithoutClosingOnEarlyError('find', TypeError);

// `Iterator.prototype.find` method
// https://tc39.es/ecma262/#sec-iterator.prototype.find
$({ target: 'Iterator', proto: true, real: true, forced: findWithoutClosingOnEarlyError }, {
  find: function find(predicate) {
    anObject(this);
    try {
      aCallable(predicate);
    } catch (error) {
      iteratorClose(this, 'throw', error);
    }

    if (findWithoutClosingOnEarlyError) return call(findWithoutClosingOnEarlyError, this, predicate);

    var record = getIteratorDirect(this);
    var counter = 0;
    return iterate(record, function (value, stop) {
      if (predicate(value, counter++)) return stop(value);
    }, { IS_RECORD: true, INTERRUPTED: true }).result;
  }
});