如何使这个庞大的Ruby if/elsif语句更紧凑,更清晰？

Question

以下if/elsif语句显然是一个庞然大物.其目的是基于用户是否填写了某些数据来更改某些文本的措辞.我觉得必须有一个更好的方法来做到这一点,而不占用30多行代码,但我只是不确定,因为我试图根据可用的数据相当显着地自定义文本.

if !birthdate.blank? && !location.blank? && !joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} in #{location}. #{sex} passed away on #{death.strftime("%B %e, %Y")} at the age of #{calculate_age(birthdate, death)}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{distance_of_time_in_words(joined,death)}.</p>"
elsif !birthdate.blank? && !location.blank? && !joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} in #{location} and is #{time_ago_in_words(birthdate)} old. #{sex} has been a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{time_ago_in_words(joined)}.</p>"
elsif birthdate.blank? && !location.blank? && !joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born in #{location}. #{sex} passed away on #{death.strftime("%B %e, %Y")}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{distance_of_time_in_words(joined,death)}.</p>"
elsif birthdate.blank? && !location.blank? && !joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born in #{location}. #{sex} has been a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{time_ago_in_words(joined)}.</p>"
elsif birthdate.blank? && location.blank? && !joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{distance_of_time_in_words(joined,death)}. #{sex} passed away on #{death.strftime("%B %e, %Y")}.</p>"
elsif birthdate.blank? && location.blank? && !joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} has been a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{time_ago_in_words(joined)}.</p>"
elsif !birthdate.blank? && location.blank? && !joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")}. #{sex} passed away on #{death.strftime("%B %e, %Y")} at the age of #{calculate_age(birthdate, death)}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{distance_of_time_in_words(joined,death)}.</p>"
elsif !birthdate.blank? && location.blank? && !joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} and is #{time_ago_in_words(birthdate)} old. #{sex} has been a member of #{link_to user.login, profile_path(user.permalink)}'s family for #{time_ago_in_words(joined)}.</p>"
elsif !birthdate.blank? && !location.blank? && joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} in #{location}. #{sex} passed away on #{death.strftime("%B %e, %Y")} at the age of #{calculate_age(birthdate, death)}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
elsif !birthdate.blank? && !location.blank? && joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} in #{location} and is #{time_ago_in_words(birthdate)} old. #{sex} is a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
elsif !birthdate.blank? && location.blank? && joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")}. #{sex} passed away on #{death.strftime("%B %e, %Y")} at the age of #{calculate_age(birthdate, death)}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
elsif !birthdate.blank? && location.blank? && joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} and is #{time_ago_in_words(birthdate)} old. #{sex} is a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
elsif birthdate.blank? && !location.blank? && joined.blank? && !death.blank?
  "<p class='birthinfo'>#{name} was born in #{location}. #{sex} passed away on #{death.strftime("%B %e, %Y")}. #{sex} was a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
elsif birthdate.blank? && !location.blank? && joined.blank? && death.blank?
  "<p class='birthinfo'>#{name} was born in #{location}. #{sex} is a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
else
  "<p class='birthinfo'>#{name} is a member of #{link_to user.login, profile_path(user.permalink)}'s family.</p>"
end

Answer 1

我认为您希望使所有这些条件更具可读性,并消除逻辑检查和字符串创建中存在的重复.

我注意到的第一件事是你在整个地方重复这个:

<p class='birthinfo'>#{name} was born in

我会尝试将这些因素分解为带参数和返回格式化文本的函数,或者计算成表达式的类.

你也没有充分利用筑巢的优势.而不是让每个条件检查四个表达式的值,你应该尝试这样的事情:

if birthdate.blank?
    # half of your expressions
else
    # other half of your expressions

它可能不会使您的代码更具可读性,但值得尝试.我建议的最后一件事是你可以巧妙地重新排列你的文本,这样它很容易分段构造,并且仍然可以很好地读取最终用户.这是一个例子:

notice = "#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")} in #{location}."

生成此代码的一个代码段可能是:

notice = "#{name} was born on #{birthdate.strftime("%A, %B %e, %Y")}"
if !location.is_blank? 
    notice += " in #{location}"
end
notice += "."

这更容易阅读你所拥有的类似代码,它将分别检查每个条件并根据布尔变量的值创建一个完全不同的字符串.您现在拥有的逻辑最糟糕的部分是,如果添加第五个变量,则必须在代码中添加更多特殊情况.将代码构建为独立的部分将更容易阅读和维护.