Ruby-on-rails rake 任务中的 def 块
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def block in rake task
提问by Victor
I got undefined local variable or method 'address_geo' for main:Objectwith the following rake task. What's the problem with it?
我得到undefined local variable or method 'address_geo' for main:Object了以下耙任务。它有什么问题？
include Geokit::Geocoders
namespace :geocode do
desc "Geocode to get latitude, longitude and address"
task :all => :environment do
@spot = Spot.find(:first)
if @spot.latitude.blank? && [email protected]?
puts address_geo
end
def address_geo
arr = []
arr << address if @spot.address
arr << city if @spot.city
arr << country if @spot.country
arr.reject{|y|y==""}.join(", ")
end
end
end
回答by rubyprince
You are defining the method inside the rake task. For getting the function, you should define outside the rake task (outside the task block). Try this:
您正在定义 rake 任务中的方法。为了获得该函数，您应该在 rake 任务之外（在任务块之外）定义。尝试这个：
include Geokit::Geocoders
namespace :geocode do
desc "Geocode to get latitude, longitude and address"
task :all => :environment do
@spot = Spot.find(:first)
if @spot.latitude.blank? && [email protected]?
puts address_geo
end
end
def address_geo
arr = []
arr << address if @spot.address
arr << city if @spot.city
arr << country if @spot.country
arr.reject{|y|y==""}.join(", ")
end
end
回答by Hula_Zell
Careful: Methods defined in rake files end up defined on the global namespace.
小心：在 rake 文件中定义的方法最终定义在全局命名空间中。
I would propose to extract the methods into a module or class. This is because methods defined in rake files end up defined on the global namespace. i.e. they can then be called from anywhere, not just within that rake file (even if it is namespaced!).
我建议将方法提取到模块或类中。这是因为在 rake 文件中定义的方法最终在全局命名空间中定义。即它们可以从任何地方调用，而不仅仅是在那个 rake 文件中（即使它是命名空间的！）。
This also means that if you have two methods with the same name in two different rake tasks, one of them will be overwritten without you knowing it. Very deadly.
这也意味着如果您在两个不同的 rake 任务中有两个同名的方法，其中一个将在您不知情的情况下被覆盖。非常致命。
A great explanation is available here: https://kevinjalbert.com/defined_methods-in-rake-tasks-you-re-gonna-have-a-bad-time/
这里有一个很好的解释：https: //kevinjalbert.com/defined_methods-in-rake-tasks-you-re-gonna-have-a-bad-time/
