Differences

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--- java-script:hoisting [2023/08/08 23:57] – odefta
+++ java-script:hoisting [2023/08/09 00:32] (current) – odefta
@@ Line 4: / Line 4: @@
 ===== Variable hoisting =====
+==== Using var keyword ====
 ;;;The variable declaration using var is hoisted, but the initialization is not.;; So, if you reference a variable before it's initialized, it will return undefined. \\
@@ Line 24: / Line 26: @@
 Hoisting does not apply to variables declared with **let** and **const**; trying to access them before their declaration will result in a **ReferenceError**.
 </note>
+==== Without any keyword ====
+;;;Variables that are declared without any keyword;;; (such as var, let, or const) ;;;are not hoisted;;;. Rather, **they become global variables** (if not already within a global scope), and their declaration and initialization happen at the line where they are assigned. \\
+Example:
+<code javascript>
+console.log(myVar); // ReferenceError: myVar is not defined
+myVar = "abc";
+console.log(myVar); // "abc"
+</code>
+In this case, **myVar** is not declared or initialized before the first console.log, so attempting to access it results in a **ReferenceError**.\\ \\
+If you were to declare the variable without initializing it within a function, **it would be hoisted as a property of the global object** (such as window in a browser environment):
+<code>
+function myFunction() {
+  myVar = "abc";
+}
+myFunction();
+console.log(window.myVar); // "abc" in a browser environment
+</code>
+This behavior can lead to unexpected results and make the code harder to understand and maintain.
 ===== Functions =====