From: Ryan Ingram <ryani.spam@...>
Date: 2008-01-29T11:20:13+09:00
Subject: Re: what's the diff between puts y and puts "#{y}" in class_

On 1/28/08, Raj Singh <neeraj.jsr@gmail.com> wrote:
> Could you please further elaborate on that. To me it  seems like both of
> them have the same scope because they are both being used in the same
> method.

Compare to this:

class T
    def first
        "hello"
    end
    def second
        "chunky bacon"
    end
end

y = "first"

T.class_eval <<-END
    def hello
        puts #{y}
    end
END

T.new.hello # prints "hello"

The key is that the "<<-END" is creating an interpolated string in the
original context; the interpolation of #{y} isn't happening during the
call to "hello", but rather as part of the string passed to
class_eval.

You are probably confused by the fact that in the sample code, the
interpolation is happening inside of another string constant, which
makes it look like it's happening as part of "hello".  It's not.

  -- ryan