Methods

Methods in Ruby

Define a method with def and close it with end:

def greet(name)
  puts "Hello, #{name}!"
end

greet("Alice")  # Hello, Alice!

Return Values

The last expression in a method is automatically returned — no return keyword needed:

def square(n)
  n * n
end

puts square(5)  # 25

You can also use return explicitly to exit early.

Default Parameters

Parameters can have default values:

def greet(name, greeting = "Hello")
  "#{greeting}, #{name}!"
end

puts greet("Alice")         # Hello, Alice!
puts greet("Bob", "Hi")    # Hi, Bob!

Your Task

Write a method full_name(first, last, separator = " ") that returns the full name with the separator between first and last.

Print full_name("John", "Doe") and full_name("John", "Doe", "_").