javascript is in list code example

Example 1: check items in array javascript

function checkAllEven(arr) {
  return arr.every(function(x){
	 return	x % 2 === 0
	})
}

//using "every" to check every item in array.

Example 2: is value in list javascript

function inListBoolean(list, item){
    var boolean = false
    list.forEach(value => {
        if(value == item){
            boolean = true
        }
    })
    return boolean;
}