Records (was Re: [Haskell] Improvements to GHC)

[Keean Schupke]

you can always do:


    case (field1 record,field2 record, field3 record ...) of
       (pat1,pat2,pat3) ->
       _ ->

Which lets you pattern match on fields independantly of their
position in the record.

    Keean.

David Roundy wrote:

>On Wed, Nov 23, 2005 at 02:58:43PM +0100, Wolfgang Jeltsch wrote:
>  
>
>>Am Mittwoch, 23. November 2005 14:22 schrieb David Roundy:
>>    
>>
>>>On Tue, Nov 22, 2005 at 02:32:47PM +0000, Rob Ennals wrote:
>>>[...]
>>>      
>>>
>>>>7. Unordered records: yep (if I understand the problem correctly)
>>>>        
>>>>
>...
>  
>
>>You can just omit the data constructors from the module's export list.
>>    
>>
>
>Yes, you can do that if you don't want to allow pattern matching.  That's
>an acceptable solution for truly "exported" (i.e. opaque) data, but for
>internal data structures I would like to allow pattern matching without
>allowing positional matching (or constructing).  Too many times I've had to
>go through the entire code adding an extra "_" to each pattern match, and
>each time there's a possibility you'll add it in the wrong spot.  I could
>do this with coding guidelines, but I'd prefer to have the compiler enforce
>this.
>  
>