Fergus Henderson <[EMAIL PROTECTED]> writes on 1 Jun 2000
>> 'n' :: Char does not hold a name in the constructor name space.
> Yes, but it is also far from self-expanatory. With a constructor
> name, in a suitable environment you could just click on the
> constructor name and the environment would immediately pop up the
> declaration and documentation for that constructor and the type that
> it belongs to.
> [..]
>> [..]
>> data Mode_sort = Sort_quick | Sort_merge | Sort_insert | Sort_other
>> deriving(Eq,Ord,Enum,Show,Read)
>> ...
>> Again, `Positive' would not do, it should be something like
>> QuotRem_Positive, and so on.
> This is a problem with Haskell, IMHO.
>
> Mercury allows overloading of constructor names, so in Mercury you
> could use just `Positive' rather than `QuotRem_Positive'. The type
> checker will resolve the ambiguity whenever possible.
This is my wish for Haskell-2: overloded constructor names.
In many cases, these name overlaps can be resolved.
>> f x y b = myRem 'c' ((myRem '_' x b)*(myRem '_' y b)) b
>>
>> Now, it has to be, maybe, remP = rem QuotRem_positive
>> remO = rem QuotRem_other
>> f x y = remP ((remO x b)*(remO x b)) b
>> Maybe, Char is better?
> No, IMHO Char would definitely not be better.
> In this case, I think separate functions would be best,
> a single function with a properly typed mode argument second best,
> and a single function with a `Char' mode argument worst.
About the type constructor for mode, I half-agree.
But about a single function - no.
If you require the single functions
sort_merge, sort_insert, sort_quick,
do you also require
tar_x, tar_xv, tar_v instead of tar <mode>
?
As to quotRem - diveRem, it has the three extra friends to export.
------------------
Sergey Mechveliani
[EMAIL PROTECTED]
