refactoring_ruby.rb

# Refactoring conditional logic using short-circut evaluation and ruby implicit return

# before refactor
def straight_flush?(array)
  if straight?(array) and flush?(array)
    return true
  else
    return false
  end
end

# after refactor
def straight_flush?(array)
  straight?(array) && flush?(array)
end


#######################################################################################################################


# Refactoring conditional logic using case statement and ruby range operator for readability

# before refactor 
def calculate_ovulation_risk(day)
  if day >= 1 && <= 5
    'very unlikely'
  elsif day >= 6 && <= 10
    'unlikely'
  elsif day >= 11 && <= 13
    'likely'
  elsif day >= 14 && <= 16
    'very likely'
  elsif day >= 17 && <= 19
    'likely'
  elsif day >= 20 && <= 25
    'unlikely'
  elsif day >= 26 && <= 28
    'very unlikely'
  end
end

# after refactor
def calculate_ovulation_risk(day)
  case day
  when 1..5
    'very unlikely'
  when 6..10
    'unlikely'
  when 11..13
    'likely'
  when 14..16
    'very likely'
  when 17..19
    'likely'
  when 20..25
    'unlikely'
  when 26..28
    'very unlikely'
  else
    'very unlikely'
  end
end


#########################################################################################################################


# Refactoring case statement to utilize a hash and reduce lines of code

# Before refactor
case params[:student_level]
when :freshman, :sophomore then
  student = Student::Underclassman.new(name, birthdate,
    address, phone)
when :junior, :senior then
  student = Student::Upperclassman.new(name, birthdate,
    address, phone)
when :graduate
  student = Student::Graduate.new(name, birthdate,
    address, phone)
else
  student = Student::Unregistered.new(name, birthdate,
    address, phone)
end

# halfway there...
klass = case params[:student_level]
        when :freshman, :sophomore then
          Student::Underclassman
        when :junior, :senior then
          Student::Upperclassman
        when :graduate
          Student::Graduate
        else
          Student::Unregistered
        end
student = klass.new(name, birthdate, address, phone)

# boom
STUDENT_LEVELS = Hash.new(Student::Unregistered).merge(
    freshman:  Student::Underclassman,
    sophomore: Student::Underclassman,
    junior:    Student::Upperclassman,
    senior:    Student::Upperclassman,
    graduate:  Student::Graduate
  )

klass = STUDENT_LEVELS[params[:student_level]]
student = klass.new(name, birthdate, address, phone)