On 24/02/10 18:23, Ian Lynagh wrote:
On Tue, Feb 23, 2010 at 07:07:30PM -0800, Iavor Diatchki wrote:
I'd like to propose that we add record punning to Haskell 2011.
Thoughts, objections, suggestions?
I have a feeling I'm in the minority, but I find record punning an ugly feature.
Given data T = C { f :: Int } we implicitly get f :: T -> Int which punning shadows with f :: Int whereas I generally avoid shadowing completely.
While I agree with these points, I was converted to record punning (actually record wildcards) when I rewrote the GHC IO library. Handle is a record with 12 or so fields, and there are literally dozens of functions that start like this: flushWriteBuffer :: Handle -> IO () flushWriteBuffer Handle{..} = do if I had to write out the field names I use each time, and even worse, think up names to bind to each of them, it would be hideous. There are reasons to find this distasteful, yes, but I think the alternative is much worse. I'm not proposing record wildcards (yet) *cough* labelled-field wildcards, but punning is a step in the right direction. Cheers, Simon