Control Flow

If and else

Ruby modifiers and blocks are both common.

score = 82
if score >= 70
  puts "passed"
else
  puts "retry"
end

puts "ok" if score >= 70

Case expressions

case compares values cleanly.

day = "sat"
kind = case day
       when "sat", "sun" then "weekend"
       else "weekday"
       end
puts kind

While and times

Use iterators when you can; while remains available.

3.times { |i| puts i }
n = 3
while n > 0
  puts n
  n -= 1
end

Flow tips

• Everything has a value—including if and case
• Prefer each over manual index loops
• next and break control iteration
• Nil is falsy; only false and nil are falsy