Indeed. GHC's existing strictness analyser answers precisely this question too -- that's not the point. The question is what it does with the information. At the moment the info flows upwards to x's binding site. What's wanted here is to make it flow downwards to x's uses. S | -----Original Message----- | From: Alastair Reid [mailto:alastair@reid-hoffmann.net] | Sent: 25 June 2004 09:37 | To: glasgow-haskell-users@haskell.org | Cc: Simon Peyton-Jones; Ian Lynagh | Subject: Re: Strictness confusion | | On Friday 25 June 2004 09:17, Simon Peyton-Jones wrote: | > b) Adding a new top-down sweep to the strictness analyser. | > (e.g. "what demand is placed on x by evaluating (f (g x))?"). | | IIRC, the Yale Haskell compiler did this kind of thing. I joined the Yale | team late in the development so I don't know how effective it was or what the | interesting issues were but there's plenty of papers/ research reports about | Yale's strictness analysis and optimization. | | -- | Alastair Reid