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That Is An Byte of Me

莎士比亚说 80%的bug，都可以通过阅读文档来解决

亚里士多德说 另外20%的bug 可以通过单元测试来定位

找bug

nshuffledCards 概率平均返回n张牌，如果n大于牌的总数，在返回全部随机排序的.

var nshuffledCards = (function () {
    var cards = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    function swap(i, j) {
        temp = cards[i]
        cards[i] = cards[j]
        cards[j] = temp
    }
    return function (n) {
        var _n = lo.min(n, cards.length)
        var result = []
        for (var i = 0; i < _n; i++) {
            var select = lo.random(i, _n - 1)
            swap(i, select)
            result.push(cards[i])
        }
        return result
    }
})()
console.log(nshuffledCards(1))

###再给点提示 如果执行

$ node untitled.js
FATAL ERROR: JS Allocation failed - process out of memory

读文档

_.min(collection, [iteratee], [thisArg])

Arguments

1. collection (Array

   Object

   string): The collection to iterate over.

2. [iteratee] (Function

   Object

   string): The function invoked per iteration.

3. [thisArg] (*): The this binding of iteratee.

min传入的第一个参数是一个集合. 如果传入的参数不对会如何呢？

> lo.min(1,2)
Infinity

结论

如果你写代码,不看文档,又不写单元测试,那么bug无处不在. 别问我为什么知道这些.