Conditionals (if, unless & case)

💎 Ruby Lesson 4 Beginner

Conditionals control the branch paths of execution based on boolean checks. Ruby provides clean readability options like the unless keyword and statement modifiers.

1 Unless Keywords & Statement Modifiers

Ruby conditionals include readability-focused enhancements:

unless Statement: The exact opposite of an `if` statement. Executes code blocks only if a condition evaluates to **false**: `unless user.logged_in? { login }`.
Statement Modifier Shorthand: You can append conditionals to the end of a single-line expression to write cleaner, more readable code: `puts "Welcome" if user.admin?`.

2 Conditional Codes

Let's run a program evaluating conditions and checking unless clauses:

Ruby — Conditionals ▶ Run Code

score = 85

# Standard if-elsif structure
if score >= 90
  puts "Grade: A"
elsif score >= 80
  puts "Grade: B"
else
  puts "Grade: F"
end

# Unless clause
is_admin = false
unless is_admin
  puts "Access restricted to admins!"
end

# Statement Modifier
is_member = true
puts "Discount Applied!" if is_member

3 Code Challenge

Challenge: Write a script using a `case` statement (with `when` and `else`) that evaluates an integer rating (1-5) and outputs descriptive feedback for each score.