How do you access variables which are defined in an included file?
# inc.rb
foo = \"bar\";
# main.rb
require \'inc.rb\'
puts foo
# NameError: undefined lo
You can't access a local outside of the scope it was defined in — the file in this case. If you want variables that cross file boundaries, make them anything but locals. $foo, Foo and @foo will all work.
If you just really don't want to put any sort of decoration on the symbol (because you don't like the way it reads, maybe), a common hack is just to define it as a method: def foo() "bar" end.