Proposal #1464: add dropPrefix to Data.List

Cale Gibbard cgibbard at
Fri Jun 29 15:21:59 EDT 2007

I agree regarding Maybe, but in the long run, I really think we should
bring back MonadZero. This issue comes up all the time because there's
not really a proper class for monads that do handle failure gracefully
any more. I personally consider 'fail' to be a wart, and mostly try to
ignore that it even exists. Monad really isn't the class for
expressing computations which might fail.

 - Cale

On 27/06/07, Iavor Diatchki <iavor.diatchki at> wrote:
> Hi,
> I can see how this function can be useful.  However, I am strongly
> opposed to adding the general monadic version---not all monads support
> graceful failure, and for monads that do not support it, the only
> option is to throw a run-time exception, which is at odds with the
> purity of Haskell (which leads to headaches when you try to write
> robust code).  I think that the "Maybe" version is perfectly adequate
> but if we have to have an overloaded version, then we should use
> "MonadPlus".
> -Iavor
> On 6/26/07, Bryan O'Sullivan <bos at> wrote:
> > Chris Smith wrote:
> >
> > > Hmm.  That would replace a function I write today if only it were:
> >
> > +1 on the monadic variant, of which I have a copy just like Chris's.
> >
> >         <b

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