Question

I’d like to access the source of a class like so:

# Module inside file1.rb
module MetaFoo
  class << Object
    def bar
      # here I'd like to access the source location of the Foo class definition
      # which should result in /path/to/file2.rb
    end
  end
end

# Class inside another file2.rb
class Foo
  bar
end

I could do something bad like:

self.send(:caller)

and try to parse the output, or even:

class Foo
  bar __FILE__
end

But that’s not, want I want, I had the hope there is a more elegant solution for that.

Any hints are welcome.

Answer 1

You could try calling:


caller.first


That will print off the file name and line number. Using your demonstration files above (with slight modifications:

file1.rb:

module MetaFoo
  class << Object
    def bar
      puts caller.first # <== the magic...
    end
  end
end

file2.rb:

require './file1.rb'

class Foo
  bar
end

When I run ruby file2.rb, I get the following output:

nat$ ruby file2.rb 
file2.rb:4:in `<class:Foo>'

That’s what you want, right?