set.rb

my_set = JillSet.new

my_set.insert("alex") # returns true
my_set.insert("jill") # returns true

my_set.has?("jill") # returns true
my_set.has?("Jill") # returns false

my_set.items # returns ["alex", "jill"]

my_set.insert("jill") # returns false
my_set.has?("jill") # returns true

my_set.remove("jill") # returns true
my_set.remove("jill") # returns false

my_set.items # returns ["alex"]

my_set.empty? # returns false
my_set.clear! # returns nil (doesn't explicitly return anything)
my_set.empty? # returns true
my_set.items # returns []