Prelude function suggestions
t.zielonka at students.mimuw.edu.pl
Thu Jul 29 08:11:08 EDT 2004
On Thu, Jul 29, 2004 at 01:57:51PM +0200, Marcin 'Qrczak' Kowalczyk wrote:
> W liście z czw, 29-07-2004, godz. 13:39 +0200, Tomasz Zielonka napisał:
> > Have you looked at List.unfoldr? It's even more general.
> > unfoldr :: (b -> Maybe (a, b)) -> b -> [a]
> And when we finally find a very general solution, the specific case of
> "split colon-separated fields" requires some thought and three lines of
> code using higher order functions and pattern matching, instead of just
> splitSep (== ':') line
> Make simple things easy, complex things possible. Concentrate on the
> first part. Generalize only if it doesn't make the common simple case
> harder. After all, one always can write a complex splitting function
> by hand. The simple version doesn't have to cover all possible
> generalizations, only those which don't disturb common cases.
I agree. I often found that writing a splitting function with unfoldr
is a bit cumbersome.
.signature: Too many levels of symbolic links
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