27 lines
512 B
JavaScript
27 lines
512 B
JavaScript
function findIndex(array, predicate, self) {
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var len = array.length;
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var i;
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if (len === 0) return -1;
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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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if (self) {
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for (i = 0; i < len; i++) {
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if (predicate.call(self, array[i], i, array)) {
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return i;
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}
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}
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} else {
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for (i = 0; i < len; i++) {
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if (predicate(array[i], i, array)) {
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return i;
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}
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}
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}
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return -1;
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}
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module.exports = findIndex
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