I'm in a little trouble here. Can't really resolve this problem, I've been using this solution:
Array.prototype.all = function(callback){
for(let i = 0; i < this.length; i++){
if(this[i] < 10) return true;
}
if(this[i] < 2) return false;
}
}
But it does not work. I know I'm making a rookie mistake (I'm new to learning javascript), and would love a little help on this.
The problem in question is this one:
function all(fn) {
// Write a function called all in the Array prototype,
// that receives a function (callback). Assume fn always returns true or false.
// The function all must return true if fn returns true when we invoke it passing all the elements of the array one by one
// the function all must return false, if any element of the array causes fn to return false;
// E.g:
// [1,2,3].all(function(elem) {
// return elem < 10;
// });
// returns true
// [1,2,3].all(function(elem) {
// return elem < 2;
// });
// returns false.
}
You only have to return true if the returned value from callback is false else return true
Array.prototype.all = function (callback) {
for (let i = 0; i < this.length; ++i) {
const result = callback(this[i]);
if (!result) return false;
}
return true;
};
const arr1 = [1, 2, 3, 4, 20, 300, 0];
const arr2 = [1, 0];
console.log(arr1.all((elem) => elem < 2));
console.log(arr2.all((elem) => elem < 2));ADDITIONAL INFO
Array.prototype already has every method that will the exact same thing
const arr1 = [1, 2, 3, 4, 20, 300, 0];
const arr2 = [1, 0];
console.log(arr1.every((elem) => elem < 2));
console.log(arr2.every((elem) => elem < 2));