Question 1: Variable Scope and Hoisting

(function(){
  var a = b = 5;
})();
console.log(b);

Expected Output:

5

Follow-Up Questions:

• Why does b exist outside the IIFE (Immediately Invoked Function Expression)?
• How does variable assignment without var, let, or const affect scope?
• What is the scope of variables a and b in this context?

Explanation:

• The line var a = b = 5; assigns 5 to b and then assigns b to a. However, b is not declared with var, let, or const, making it a global variable.
• Variable a is function-scoped due to var, so it is not accessible outside the IIFE.
• Accessing b outside the function logs 5 because it becomes a property of the global object.

Question 2: Floating-Point Precision

console.log(0.1 + 0.2 === 0.3);

Expected Output:

false

Follow-Up Questions:

• Why does the expression return false when mathematically it should be true?