[Haskell-cafe] Is "take" behaving correctly?

[Derek Elkins]

On Tue, 2007-09-11 at 16:48 -0700, Don Stewart wrote:
> byorgey:
> >    On 9/11/07, Don Stewart <[1]dons at galois.com> wrote:
> > 
> >      byorgey:
> >      >    On 9/11/07, PR Stanley <[1]prstanley@[2]ntlworld.com> wrote:
> >      >
> >      >      Hi
> >      >      take 1000 [1..3] still yields [1,2,3]
> >      >      I thought it was supposed to return an error.
> >      >      Any ideas?
> >      >      Thanks, Paul
> >      >
> >      >    If for some reason you want a version that does return an error in
> >      that
> >      >    situation, you could do something like the following:
> >      >
> >      >    take' n _ | (n <= 0) = []
> >      >    take' n [] | (n > 0) = error "take': list too short"
> >      >               | otherwise = []
> >      >    take' n (x:xs) = x : take' (n-1) xs
> > 
> >      And we'd call it unsafeTake, just like unsafeFromJust and unsafeTail :-)
> > 
> >      -- Don
> > 
> >    Hmm, that's funny, I don't recall ever hearing of those functions... =)
> > 
> >    ooo, Don has a shiny new e-mail address!
> > 
> 
> And a shiny new job in a shiny new city :-)

In a   new country.