Re: Records in Haskell

On 02/28/2012 06:40 AM, AntC wrote:

Oliver Batchelor writes:

...

Perhaps this situation could occur though?

Module A fieldLabel name String

Module B import A -- unknowingly picking up the name label

data Foo = Foo { name :: String } -- uses the name label by accident

So there'd have to be some syntax to make sure you intend to use a label rather than accidentally use it? (Not that this is a big issue, the situation is surely minor compared to sharing unrelated labels all the time)

Oliver

Thanks Oliver, hmm ...

Oliver's example is exactly what I feel weird about (and what I refered to as a "magical effect"). Sorry for failing to communicate to you successfully. In the meantime, I had an idea (that could work with SORF or DORF) : data Foo = Foo { name :: String } deriving (SharedFields) The effect is: without that "deriving", the declaration behaves just like H98. (For super flexibility, allow to specify which fields are shared, like "deriving(SharedFields(name, etc, etc))" perhaps.) Is it too verbose? Or too terrible that it isn't a real class (well, there's Has...)? -Isaac