详解JavaScriptes6的新增数组方法

		let arr = ["a", "b", "c", 1, 2, 3];
        
        arr.forEach((value, index, arr) => {
            console.log(value, index, arr);
        })

let arr = [1,2,3,4,5]
let arr1 = arr.filter( (value, index) => value%2 === 0)
console.log(arr1)    // [2, 4]

let arr = [1,2,3,4,5]
let arr1 = arr.every( (value, index) =>value<2)
console.log(arr1) // false
let arr2 = arr.every( (value, index) =>value<6)
console.log(arr2)  // true

let arr = [1,2,3,4,5]
arr.map( (value,index,array)=>{
        value = value * 2
        console.log(`value:${value}    index:${index}     array:${array}`)
})   
console.log(arr)

var arr1 = [1,2,3,4]; 
var res1 = arr1.map((item,index,arr)=>{ 
 item = item * 3; 
 return item; 
})
console.log(arr1); // [1,2,3,4]
console.log(res1); // [3,6,9,12]

let arr = [1,2,3,4,5]
let arr1 = arr.some( (value, index) => value < 3)
console.log(arr1) // true
let arr2 = arr.some( (value, index) => value > 6)
console.log(arr2) // false