创建一个移除了所有假值的数组。例如：false、null、 0、""、undefined， 以及NaN 都是 “假值”.
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<title>移除假值数组</title>
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<script src="https://cdn.bootcss.com/lodash.js/4.17.10/lodash.min.js"></script>
<script type="text/javascript">
var aa = _.compact([0, 1, false, 2, '', 3]); console.log(aa); //[1,2,3]
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