// var hoisting
num; // => undefined
var num;
num = 10;
num; // => 10
// function hoisting
getPi; // => function getPi() {...}
getPi(); // => 3.14
function getPi() {
return 3.14;
}
function multiplyByTen(number) {
console.log(ten); // => undefined
var ten;
ten = 10;
console.log(ten); // => 10
return number * ten;
}
multiplyByTen(4); // => 40
function sumArray(array) {
return array.reduce(sum);
function sum(a, b) {
return a + b;
}
}
sumArray([5, 10, 8]); // => 23
let condition = true;
if (condition) {
// console.log(number); // => Throws ReferenceError
let number;
console.log(number); // => undefined
number = 5;
console.log(number); // => 5
}
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