as a follow up of another question here, i have added the following code to my records\_controller.rb

```
if params[:order].in? %s[year artist title]
  # adds ORDER to the scope
  @records.merge!( Record.order("? DESC", params[:order]) )
end

```

but then i got an error:

```
"The parameter passed to #in? must respond to #include?"

```

what does this mean? What do i need to change?