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lodash源码分析之head #38

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HeftyKoo opened this issue Aug 30, 2019 · 0 comments
Open

lodash源码分析之head #38

HeftyKoo opened this issue Aug 30, 2019 · 0 comments
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api 暴露出来的接口 系列文章

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@HeftyKoo
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本文为读 lodash 源码的第三十七篇,后续文章会更新到这个仓库中,欢迎 star:pocket-lodashgitbook也会同步仓库的更新,gitbook地址:pocket-lodash

源码分析

headlast 刚好相反,获取的是数组第一项。

其实如果知道输入项一定是数组,直接使用 array[0] 来获取也很简单,head 方法主要做了一些非空的判断操作。

function head(array) {
  return (array != null && array.length)
    ? array[0]
    : undefined
}

last 的源码分析如下:

lodash源码分析之last

License

署名-非商业性使用-禁止演绎 4.0 国际 (CC BY-NC-ND 4.0)

最后,所有文章都会同步发送到微信公众号上,欢迎关注,欢迎提意见:

作者:对角另一面

@HeftyKoo HeftyKoo added 系列文章 api 暴露出来的接口 labels Aug 30, 2019
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