# File lib/sass/stack.rb, line 101 def to_s Sass::Util.enum_with_index(Sass::Util.enum_cons(frames.reverse + [nil], 2)). map do |(frame, caller), i| "#{i == 0 ? 'on' : 'from'} line #{frame.line}" + " of #{frame.filename || 'an unknown file'}" + (caller && caller.name ? ", in `#{caller.name}'" : "") end.join("\n") end