Containers and strictness continued

[Felipe Lessa]

On Fri, Jul 9, 2010 at 6:56 AM, Milan Straka <fox at ucw.cz> wrote:
> Hi all,
>
> for my work on the containers I need to settle some questions about strictness.
> Thank you very much for your opinions.

Thanks for looking into this! =)

> Discussion ends: 23. July 2010.
>
> 1) Strictness of keys and values in the datatype.
>
> Currently we have the following strictness flags in the datatypes:
> - IntMap: !key value
> - IntSet: !key
> - Map: !key value
> - Set: key
>
> I vote for changing Set to store keys also strict.
>
> Storing values as nonstrict probably makes sense.

+1 for strict Set keys

> 2) Strictness of keys and values in the method definitions.
>
> The IntMap.lookup (lookup k t = ... seq k ...) evaluates the given key
> even if it is not needed (when searching empty tree). Some methods are
> more carefull.
>
> I vote for all IntMap, IntSet, Map and Set methods that are given a key
> value (insert, delete, member, ...) to be strict in the keys. This
> a) would be consistent with 1)
> b) would be a bit more efficient (~5% in the IntMap.lookup case)

+1 for strictness in keys on all functions.

> 3) Strict folds
>
> Currently there are no strict folds.
>
> I vote for adding strict folds (fold', foldWithKey' when appropriate) to
> all Map, Set, IntMap, IntSet.

Not sure about this one, but it's probably +1 as well.

Cheers,

-- 
Felipe.