documentit/node_modules/array-find-index/index.js

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2018-01-05 18:48:13 +00:00
'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;
};