05 lodash

~ yarn add loadsh

loadsh 方法： first / each / reverse / findIndex / toUpper

const _ = require("lodash");
const array = ["lucy", "lili", "kate", "lala"];
console.log(_.first(array)); 
// lucy
console.log(_.toUpper(_.first(array))); 
// LUCY
const r = _.each(array, (item, index) => console.log(item, index)); 
// lucy 0 lili 1 kate 2lala 3
console.log(r); 
// [ 'lucy', 'lili', 'kate', 'lala' ]
console.log(_.reverse(array)); 
// [ 'lala', 'kate', 'lili', 'lucy' ]
console.log(_.findIndex(array, (item) => item === "lili")); 
// 2