Conditionals

• if/elsif/else/end
• unless
• Unless you're using a one-liner then you need to end your if statement with and 'end' statement.

x = 2

if x < 3
  puts 'less than 3'
end

* Writing the same thing as a one-liner

if x < 3 then puts 'less than 3' end
puts 'less than 3' if x < 3

* Using elsif

if x < 2
  puts "less than 2"
elsif x == 2
  puts "It's two!"
else
  puts 'greater than two!'
end

• Unless
• My own personal preference is to avoid the 'not' operator and state conditions in the positive. Using the 'unless' keyword is great for this.

x = true

puts "it's true!" if x != false

unless x == false
  puts "it's true!"
end

• Unless can also be used as a one-liner

puts "it's true!" unless x == false

You cannot use elsif with unless, only else

unless x == false
  puts "it's true!"
else
  puts "it's false!"
end


unless x == false
  puts "it's true!"
elsif
  puts "it's false!"
end

#returns an error

More Examples

num_of_pizzas= 7

def num_of_slices(pizza_count)
  pizza_count * 8
end

slices_per_person = 3
total_num_of students =14

def totalslices
  num_of_slices * num_of_pizzas
end

if totalslices / 3 > 14
  puts we have enough slices!
else
  puts we dont have enough slices!
end