js 统计空格次数

Question

vara=["a","","","","b","","","c",""];计算后的结果是{
a:3,
b:2,
c:1
}

Answer 1

((a,_)=>a.reduce((p,c)=>[_=c||_,_&&[p[_]=p[_]||0,!c&&(p[_]++)],p][2],{}))(["a","","","","b","","","c",""],undefined)会忽略第一个非空字符前的所有空字符。