I can't find advice in the GHC manual on determining how much time your program spends in Prelude functions. I've discovered that I can alias a Prelude function e.g.

import Data.Set

....

myMkSet = mkSet

... which will give me a cost-centre for mkMySet. Isn't there an easier way to do this? ***************************************************************** The information in this email and in any attachments is confidential and intended solely for the attention and use of the named addressee(s). This information may be subject to legal professional or other privilege or may otherwise be protected by work product immunity or other legal rules. It must not be disclosed to any person without our authority. If you are not the intended recipient, or a person responsible for delivering it to the intended recipient, you are not authorised to and must not disclose, copy, distribute, or retain this message or any part of it. *****************************************************************