How do you communicate between Rake tasks?

Question

Let's say I have a target who needs to compile some files. That target has another target as a prerequisite, one that obtains the files. Let's say this:

task :obtain do
  # obtain files from somewhere
end

task :compile => :obtain do
  # do compilation
end

Let's say that the :obtain target doesn't always places the files in the same folder. How would I pass :compile the path that :obtain found? Environment variables?

Answer 1

Using ENV['something'] is in my opinion preferable, because if you do it this way (as opposed to $global or @instance variables) you can treat those as task arguments, and use the sub task from commandline easily.

On the other hand if you keep your code in separate classes / modules / methods, you will not even have to deal with those sorts of hacks + your code will be more testable.