数组过滤布尔值为false的值

[ckinmind]

题目来自FCC: Falsy Bouncer, 过滤数组中false, null, 0, "", undefined, and NaN 这些值，题目很简单

function bouncer(arr) {r.
 return arr.filter(function(v){
   return Boolean(v);
  });
}

bouncer([false, null, 0, NaN, undefined, ""]);

Boolean()方法可以将false, null, 0, "", undefined, and NaN,返回false

[ckinmind]

本题很简单，但是看了大神的答案每次都有新体会

function bouncer(arr) {
  // Boolean is a function so it acts as a callback here instead of Boolean(arg)
  return arr.filter(Boolean);
}

bouncer([7, "ate", "", false, 9]);

因为Boolean就是方法，可以直接当成回调函数