什么是“环境”？ Rake 中的任务？
根据“自定义 Rake 任务”：
desc "Pick a random user as the winner"
task :winner => :environment do
puts "Winner: #{pick(User).name}"
end
据我所知，：获胜者=> :environment 表示“在 winner 之前执行 environment”。但什么是环境？我应该什么时候使用它？
我尝试了rake -T，但在列表中我找不到环境。
According to "Custom Rake Tasks":
desc "Pick a random user as the winner"
task :winner => :environment do
puts "Winner: #{pick(User).name}"
end
As far as I know, the :winner => :environment means "do environment before winner". But what's environment? When should I use it?
I tried rake -T, but in the list I couldn't find environment.
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通过使任务依赖于环境任务，您可以访问您的模型，事实上，您的整个环境。这可以让您执行诸如
run rake RAILS_ENV=staging db:migrate之类的操作。请参阅“自定义 Rake 任务”。
You can get access to your models, and in fact, your whole environment by making tasks dependent on the environment task. This lets you do things like
run rake RAILS_ENV=staging db:migrate.See "Custom Rake Tasks".
它会加载到您的 Rails 环境中，以便您可以实际使用您的模型以及其他什么。否则，它对这些事情一无所知。
因此，如果您创建的任务只是
puts“HI!”，那么您不需要将:environment任务添加到依赖项中。但是，如果您希望做类似User.find(1)的事情，那么就需要它。It loads in your Rails environment so you can actually use your models and what not. Otherwise, it has no idea about those things.
So if you made a task that just did
puts "HI!"then you don't need to add the:environmenttask to the dependencies. But if you wish to do something likeUser.find(1)well that will need it.包括
=>; :environment将告诉 Rake 加载完整的应用程序环境，为相关任务提供对类、助手等的访问权限。如果没有:environment，您将无法访问任何内容这些额外的东西。还有
=>; :environment本身不提供任何与环境相关的变量，例如environment、@environment、RAILS_ENV等。Including
=> :environmentwill tell Rake to load full the application environment, giving the relevant task access to things like classes, helpers, etc. Without the:environment, you won't have access to any of those extras.Also
=> :environmentitself does not make available any environment-related variables, e.g.environment,@environment,RAILS_ENV, etc.