[Haskell-beginners] Left vs Right

[emacstheviking]

I just love the way Haskell can blow something really simple into something
truly mind blowingly obtuse looking at times!
It's no wonder Haskell won't be "mainstream" for a while yet, but that's
fine, it means the rest of us can charge better rates for now.
:)


On 15 April 2015 at 13:50, Kostiantyn Rybnikov <k-bx at k-bx.com> wrote:

> Adding to others,
>
> For fmapping left value I suggest using fmapLeft from errors package, for
> fmapping both you can use
>
> either (Left . replicate 3) (Right . replicate 3)
> 14 квіт. 2015 19:48 "Shishir Srivastava" <shishir.srivastava at gmail.com>
> пише:
>
>> Hi,
>>
>> Can someone please explain the difference in outputs of the following two
>> expressions -
>>
>> --------------
>>
>> ghci> fmap (replicate 3) (Right "blah")
>> Right ["blah","blah","blah"]
>>
>> ghci> fmap (replicate 3) (Left "foo")
>> Left "foo"
>>
>> ---------------
>>
>> Why does 'Right' return a list of Strings whereas 'Left' returns just a
>> String.
>>
>> Thanks,
>> Shishir
>>
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>>
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