Re: [Haskell-beginners] Left vs Right

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 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" пише:

...

Hi,

Can someone please explain the difference in outputs of the following two expressions -

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ghci> fmap (replicate 3) (Right "blah") Right ["blah","blah","blah"]

ghci> fmap (replicate 3) (Left "foo") Left "foo"

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Why does 'Right' return a list of Strings whereas 'Left' returns just a String.

Thanks, Shishir

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