Keep the present Haskell record system!

Bulat Ziganshin bulat.ziganshin at
Mon Mar 6 04:23:27 EST 2006

Hello Lennart,

Monday, March 6, 2006, 9:50:24 AM, you wrote:

LA> Yes, I've read the article too.  And I really like the record system.
LA> But an off-hand remark like that doesn't convince me.

my own opinion is that this scheme is like classes - they can be
resolved at compile time in most real cases but noone do it because
code will be too large. if some function can accept any records which
has field 'a' then to use this function on records of different types
we need either to do specialization or use scheme with non-constant
access time

also, while i like dynamic records for some types of tasks, i think
that the "spirit" of Haskell in whole is to give explicit definitions
of all types used and in this respect this type extension in not on
"main way". i will be glad to write smth like this:

data A = A { f1 :: Integer  -- filesize
           , f2 :: String   -- filename

data B : A = B { f3 : Int   -- filedate
               , f4 : Int   -- filetime

i.e. explcicitly define concrete types as a set of fields,
explicitly define types of fields and make comments just here. in this
respect, O'Haskell is what i really like 

Best regards,
 Bulat                            mailto:Bulat.Ziganshin at

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