19 lines
477 B
JavaScript
19 lines
477 B
JavaScript
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var hasOwn = Object.prototype.hasOwnProperty;
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module.exports = function (xs, f, acc) {
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var hasAcc = arguments.length >= 3;
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if (hasAcc && xs.reduce) return xs.reduce(f, acc);
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if (xs.reduce) return xs.reduce(f);
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for (var i = 0; i < xs.length; i++) {
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if (!hasOwn.call(xs, i)) continue;
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if (!hasAcc) {
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acc = xs[i];
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hasAcc = true;
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continue;
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}
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acc = f(acc, xs[i], i);
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}
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return acc;
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};
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