[Haskell-beginners] Meaning of (Eq a)

[Brandon S Allbery KF8NH]

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On 9/5/10 04:58 , Rohit Garg wrote:
> Although it works, my question is why ghci refuses to run it without
> the "(Eq a) => " being added to the type signature of the function.

Haskell won't do type inference if you provide a function with a type
signature, so if you say anything at all you need to say everything about
it.  If you say *nothing* about it, as with the second function, Haskell
will infer everything including required constraints.

- -- 
brandon s. allbery     [linux,solaris,freebsd,perl]      allbery at kf8nh.com
system administrator  [openafs,heimdal,too many hats]  allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university      KF8NH
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