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| 'use strict';
| module.exports = function (arr, predicate, ctx) {
| if (typeof Array.prototype.findIndex === 'function') {
| return arr.findIndex(predicate, ctx);
| }
|
| if (typeof predicate !== 'function') {
| throw new TypeError('predicate must be a function');
| }
|
| var list = Object(arr);
| var len = list.length;
|
| if (len === 0) {
| return -1;
| }
|
| for (var i = 0; i < len; i++) {
| if (predicate.call(ctx, list[i], i, list)) {
| return i;
| }
| }
|
| return -1;
| };
|
|