[Haskell-beginners] Value from Monad

Sumit Sahrawat, Maths & Computing, IIT (BHU) sumit.sahrawat.apm13 at iitbhu.ac.in
Wed Apr 22 15:25:45 UTC 2015


return (str++"4") should work

On 22 April 2015 at 20:54, Shishir Srivastava <shishir.srivastava at gmail.com>
wrote:

> Hi,
>
> Going through the '<-' description in 'learnouahaskell' it says -
>
> *" If we have a Maybe String and we bind it with <- to a variable, that
> variable will be a String"*
>
> so if you write
>
> do
> str <- Just "3"
>
> str should be of type 'String'. My question is how do I return "34"
> by concatenating it to "4" because the following line of code fails -
>
> ---
> do
> str <- Just "3"
> return str++"4"::Maybe String
> ---
>
> or for that matter how can I return/print just the value of str from this
> do block ?
>
> Thanks,
> Shishir
>
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-- 
Regards

Sumit Sahrawat
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