Question

I’m currently looking into using Rake to deploy my projects and I’m beavering away at learning Ruby/Rake. However can someone please explain to me the difference between Regular Tasks & File Tasks? This keeps getting mentioned but I have no idea the difference between the two and I can’t find a definition?

Answer 1

Martin Fowler wrote a great explanation of these features.

• http://martinfowler.com/articles/rake.html#RakeTasks
• http://martinfowler.com/articles/rake.html#FileTasks

File Tasks

The tasks I talked about above are similar to tasks in ant. Rake also supports a slightly different kind of task called a file task which is closer to the notion of tasks in make. Here’s another example, slightly simplified, from my web site rakefile.

file 'build/dev/rake.html' => 'dev/rake.xml' do |t|
  require 'paper'
  maker = PaperMaker.new t.prerequisites[0], t.name
  maker.run
end

With a file you are referring to actual files rather than task names. So ‘build/dev/rake.html’ and ‘dev/rake.xml’ are actual files. The html file is the output of this task and the xml file is the input. You can think of a file task as telling the build system how to make the output file – indeed this is exactly the notion in make – you list the output files you want and tell make how to make them.