Method naming conventions (? and ! suffixes) in Ruby - Mini Project: Build & Apply

Method naming conventions (? and ! suffixes)

📖 Scenario: You are building a simple Ruby program to check and modify strings. In Ruby, methods that end with ? usually return true or false, and methods that end with ! usually change the object itself.

🎯 Goal: You will create methods with ? and ! suffixes to practice Ruby naming conventions. You will write a method to check if a string contains vowels and another method to remove vowels from the string permanently.

📋 What You'll Learn

Create a method called contains_vowels? that returns true if the string has any vowels.

Create a method called remove_vowels! that removes vowels from the string permanently.

Use the ? suffix for the method that returns a boolean.

Use the ! suffix for the method that modifies the string.

Print the results to show the methods work as expected.

💡 Why This Matters

🌍 Real World

These naming conventions help programmers quickly understand if a method will just check something or if it will change data. This is useful when working on bigger Ruby projects or with other developers.

💼 Career

Knowing Ruby method naming conventions is important for writing clear, maintainable code. Many Ruby jobs expect you to follow these conventions to avoid bugs and improve teamwork.

1

Create a string variable

Create a variable called word and set it to the string "hello world".

Ruby

# Create a variable called word and set it to "hello world"
# Your code here

Need a hint?

Use = to assign the string to the variable word.

2

Create the contains_vowels? method

Define a method called contains_vowels? that takes a string parameter called str and returns true if str contains any vowels (a, e, i, o, u), otherwise false. Use the ? suffix in the method name.

Ruby

word = "hello world"
# Define contains_vowels? method below
# Your code here

Need a hint?

Use a regular expression to check for vowels and return true or false.

3

Create the remove_vowels! method

Define a method called remove_vowels! that takes a string parameter called str and removes all vowels from it permanently. Use the ! suffix in the method name to show it modifies the string.

Ruby

word = "hello world"
def contains_vowels?(str)
  !!(str =~ /[aeiou]/i)
end
# Define remove_vowels! method below
# Your code here

Need a hint?

Use gsub! to change the string by removing vowels.

4

Test and print the results

Call contains_vowels? with word and print the result. Then call remove_vowels! with word and print word again to show it changed.

Ruby

word = "hello world"
def contains_vowels?(str)
  !!(str =~ /[aeiou]/i)
end
def remove_vowels!(str)
  str.gsub!(/[aeiou]/i, '')
end
# Print contains_vowels?(word) result
# Call remove_vowels!(word) and print word
# Your code here

Need a hint?

Use puts to print the results.