[Haskell-cafe] parser error in pattern

[kolli kolli]

after parsing a string i am evaluating it...
string if t1 then t2 else t3
my code is
eval1 :: Term ->  Maybe Term
eval1(If Tru t2 t3) = Just t2
eval1(If Fls t2 t3) = Just t3
eval1(If t1 t2 t3) =  case eval t1
                    where eval1(If t1 t2 t3) =  Just t1

eval :: Term -> Term
eval (IsZero Zero) = Tru
eval (Zero) = Zero
eval(Pred Zero) = Pred Zero

On Mon, Oct 17, 2011 at 3:46 PM, Ivan Lazar Miljenovic <
ivan.miljenovic at gmail.com> wrote:

> On 18 October 2011 08:43, kolli kolli <nammukolli04 at gmail.com> wrote:
> > hey can anyone tell me what is parser error in parser??Plz help me out
>
> It's when the parser can't parse what it's provided.... providing the
> code that caused the problem and the actual error message is required
> for a more detailed explanation.
>
> --
> Ivan Lazar Miljenovic
> Ivan.Miljenovic at gmail.com
> IvanMiljenovic.wordpress.com
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20111017/1bfeee93/attachment.htm>