Re: [Haskell-beginners] another type problem

Also remember that Just has the type Just :: a -> Maybe a Thus putting in a Just doesn't help with your issue. On 12 May 2015 at 19:54, Sumit Sahrawat, Maths & Computing, IIT (BHU) < sumit.sahrawat.apm13@iitbhu.ac.in> wrote:

The type of the cons operator (:) is

(:) :: a -> [a] -> [a]

The way you are invoking it expects it to have the type

(:) :: a -> Maybe [a] -> [a] -- not valid

One solution is to write such a function yourself, while the other would be to rewrite your code to invoke it correctly.

On 12 May 2015 at 19:46, Brandon Allbery wrote:

...

On Tue, May 12, 2015 at 10:11 AM, Roelof Wobben wrote:

...

I do not understand what you are saying to me.

I know that init produces a Maybe [a] . That is why I did put a Just before it.

You are invoking it again though, and using its result as if it produces [a] instead of Maybe [a].

-- brandon s allbery kf8nh sine nomine associates allbery.b@gmail.com ballbery@sinenomine.net unix, openafs, kerberos, infrastructure, xmonad http://sinenomine.net

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-- Regards

Sumit Sahrawat

-- Regards Sumit Sahrawat