[Haskell-beginners] another type problem

[Alexey Shmalko]

Before cons'ing the result of init', you should check whether it's Just or
Nothing. What you're doing now is something along the line with 5 : Just 3
-- this won't typecheck.

On Tue, May 12, 2015 at 5:22 PM Roelof Wobben <r.wobben at home.nl> wrote:

>  Brandon Allbery schreef op 12-5-2015 om 16:16:
>
>  On Tue, May 12, 2015 at 10:11 AM, Roelof Wobben <r.wobben at home.nl> 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 at gmail.com
> ballbery at sinenomine.net
> unix, openafs, kerberos, infrastructure, xmonad
> http://sinenomine.net
>
>
> _______________________________________________
> Beginners mailing listBeginners at haskell.orghttp://mail.haskell.org/cgi-bin/mailman/listinfo/beginners
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>
> What is then the right way to do. I still do not understand what you are
> trying to make clear to me.
>
>
> Roelof
>
>
>
>
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