Object identity (equal? vs ==) in Ruby - Hands-On Comparison

Understanding Object Identity with equal? vs ==

📖 Scenario: Imagine you have two boxes that look the same and hold the same toys. You want to check if they are actually the same box or just two boxes with the same toys inside.

🎯 Goal: You will learn how to check if two objects are exactly the same object in memory or just look equal in Ruby using equal? and ==.

📋 What You'll Learn

Create two string variables with the same content

Create a third variable pointing to one of the first strings

Use equal? to check if two variables point to the same object

Use == to check if two variables have the same content

Print the results clearly

💡 Why This Matters

🌍 Real World

Understanding object identity helps avoid bugs when working with data that might look the same but are different objects, such as user inputs or data from files.

💼 Career

Many programming jobs require knowing when two variables refer to the same object or just equal data, especially in debugging and optimizing code.

1

Create two string variables with the same content

Create two string variables called string1 and string2 with the exact value "hello".

Ruby

# Create two string variables called string1 and string2 with the value "hello"
# Your code here

Need a hint?

Use = to assign the string "hello" to both string1 and string2.

2

Create a third variable pointing to the first string

Create a variable called string3 and set it equal to string1.

Ruby

string1 = "hello"
string2 = "hello"
# Create a variable string3 equal to string1
# Your code here

Need a hint?

Assign string3 to be the same object as string1 by using =.

3

Check object identity with equal?

Use equal? to check if string1 and string2 are the same object, and also if string1 and string3 are the same object. Store the results in variables same_object_1_2 and same_object_1_3 respectively.

Ruby

string1 = "hello"
string2 = "hello"
string3 = string1
# Use equal? to check if string1 and string2 are the same object
# Use equal? to check if string1 and string3 are the same object
# Your code here

Need a hint?

Use variable = object1.equal?(object2) to check if two variables point to the same object.

4

Print the results of equal? and ==

Print the values of same_object_1_2 and same_object_1_3. Then print the result of string1 == string2 and string1 == string3 to show if their contents are equal.

Ruby

string1 = "hello"
string2 = "hello"
string3 = string1
same_object_1_2 = string1.equal?(string2)
same_object_1_3 = string1.equal?(string3)
# Print the results of equal? and == comparisons
# Your code here

Need a hint?

Use puts with string interpolation to print the variable names and their values clearly.