On Thu, Jul 26, 2012 at 2:31 AM, Brent Yorgey
<byorgey@seas.upenn.edu> wrote:
On Wed, Jul 25, 2012 at 11:02:39PM +0200, Corentin Dupont wrote:
>
This is a little better, it avoids all the record syntax for
extracting player numbers, and uses 'any' instead of 'find' since we
don't actually care about the player with the given number if they
exist:
> addPlayer :: PlayerInfo -> State Game Bool
> addPlayer pi = do
> pls <- gets players
> let exists = any (((==) `on` playerNumber) pi) pls
> when (not exists) $ modify (\game -> game { players = pi : pls})
> return $ not exists
-Brent