Logical and Comparison Operators

Logical and comparison operators help you make decisions in Ruby programs.

In this lesson, you will learn how to use ==, !=, >, <, &&, ||, and ! operators.

Comparison Operators

Comparison operators are used to compare values.

puts 10 == 10  # true
puts 10 != 5   # true
puts 10 > 5    # true
puts 10 < 5    # false

Logical AND (&&) Operator

The && operator returns true only if both conditions are true.

puts true && true   # true
puts true && false  # false

Logical OR (||) Operator

The || operator returns true if at least one condition is true.

puts true || false  # true
puts false || false # false

Logical NOT (!) Operator

The ! operator negates a boolean value.

puts !true  # false
puts !false # true

Combining Operators

You can combine logical and comparison operators in a single expression.

age = 25
puts age > 18 && age < 30  # true

Short-Circuit Evaluation

Ruby stops evaluating an expression as soon as the result is determined.

puts true || (puts 'Not executed') # 'true' and skips the second part

The Spaceship Operator (<=>)

The <=> operator returns:

• -1 if the left operand is smaller
• 0 if both are equal
• 1 if the left operand is greater

puts 10 <=> 5   # 1
puts 10 <=> 10  # 0
puts 5 <=> 10   # -1

Congratulations!

You have learned how to use logical and comparison operators in Ruby.

Next, you will learn about methods and blocks.