iRules Recipe 4: Static Maintenance Page

I am trying to implement this recipe but I'm having syntax issues with the code you have under the "Elaboration" section (send other things like images). Specifically, I am getting syntax error related to:

set attr [class lookup [HTTP::path]] <- error: [wrong args][class lookup [HTTP::path]]

and

HTTP::respond 200 content [ifile get [getfield $attr 1 ,]] Content-Type [getfield $attr 2,] <- error: [wrong args][getfield $attr 1,], error: [wrong args][getfield $attr 2,]

For the 'getfield' errors, I believe it should be this instead:

HTTP::respond 200 content [ifile get [getfield $attr , 1]] Content-Type [getfield $attr , 2]

Can you confirm the syntax you've provided for both items I've listed above?

Thanks.