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