scopes & hoisting intro

Author: neerajforeal

js_functions/scopes.js

@@ -0,0 +1,46 @@
+// var c = 200;
+let a = 300;
+
+if (true) {
+  let a = 10;
+  const b = 20;
+  var c = 30;
+  console.log("Inside block: ", a); // 10
+}
+
+console.log(a); // 300
+//console.log(a); // ReferenceError: a is not defined
+//console.log(b); // ReferenceError: b is not defined
+console.log(c); // 30
+
+function one() {
+  const username = "Henry";
+
+  function two() {
+    const website = "youtube.com";
+    console.log(username); // Henry
+  }
+  //console.log(website); // ReferenceError: website is not defined
+  two();
+}
+one();
+
+if (true) {
+  const username = "henry";
+  if (true) {
+    const website = " youtube.com";
+    console.log(username + website);
+  }
+  //console.log(website); // ReferenceError: website is not defined
+}
+//console.log(username); // ReferenceError: username is not defined
+
+addOne(4); // 5
+function addOne(num) {
+  return num + 1;
+}
+
+addTwo(4); // ReferenceError: Cannot access 'addTwo' before initialization
+const addTwo = function (num) {
+  return num + 2;
+};