Can we stop polluting the namespace with list based function
definitions? Most of these functions: delBy, filter, map, concat, length,
take, takeWhile, etc. are well specified for data structures other than
lists. Regardless of whether Haskell includes generic programming
extensions, it would be nice to be able to use these function names for
the same operation in other datastructures (even if they are implemented
manually).
-Alex-
On Tue, 7 Dec 1999, S.D.Mechveliani wrote:
> To my proposal to add to Haskell-2 library
> delBy :: (a -> Bool) -> [a] -> [a]
>
> Keith Wansbrough <[EMAIL PROTECTED]>
> writes on 06 Dec 1999
>
> > So what do you propose as the definition for
> >
> > del :: (Eq a) => [a] -> [a]
> >
> > ?
> >
> > Section 7.6 of the Library Report:
> >
> > "By convention, overloaded functions have a non-overloaded
> > counterpart whose name is suffixed with ``By''."
>
>
> Does this really imply that having delBy, the library has
> necessarily to include `del' ?
> Anyway, let us try to improve the proposal:
> -------------------------------------------------------------------
> (1) To change in the `List' library the deleteBy definition to
>
> deleteBy :: (a -> Bool) -> [a] -> [a]
> deleteBy _ [] = []
> deleteBy p (a:as) = if p a then as else a:(deleteBy p as)
>
> deleteBy of Haskell-98 to rename to
> delByR2e (delete by binary relation (a->a->Bool) and element a).
>
> - or better to remove it at all. For its type looks esoteric.
> I wonder, who ever uses it.
>
> (2) To change in the Section 7.6 of the Library Report
> "
> By convention, overloaded functions have a non-overloaded
> counterpart whose name is suffixed with ``By''.
> "
> to
> "
> By convention, an overloaded function may have several
> non-overloaded counterparts whose names are suffixed with
> `By'[ss].
> Examples: By means "by something simplest",
> ByP by predicate,
> ByR2 by binary relation,
> ...
> "
> ---------------------------------------------------------------------
>
>
> ------------------
> Sergey Mechveliani
> [EMAIL PROTECTED]
>
>
>
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