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List:       haskell-cafe
Subject:    Re: [Haskell-cafe] hugs type inference
From:       Ross Paterson <ross () soi ! city ! ac ! uk>
Date:       2005-10-27 23:14:56
Message-ID: 20051027231456.GA25657 () soi ! city ! ac ! uk
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On Thu, Oct 27, 2005 at 11:02:48PM +0200, Christian Maeder wrote:
> Hugs.Base> :t toRational 1 / 2
> toRational 1 / 2 :: Real a => Ratio Integer
> 
> ghci yields:
> Prelude> :t toRational 1 / 2
> 
> <interactive>:1:0:
>     Warning: Defaulting the following constraint(s) to type `Integer'
>              `Real a' arising from use of `toRational' at 
> <interactive>:1:0-9
>              In the first argument of `(/)', namely `toRational 1'
> toRational 1 / 2 :: Rational

They're both telling you the same thing:

	1 :: Num a => a
	toRational 1 :: Real a => Rational
	toRational 1 / 2 :: Real a => Rational

GHCi shows the type after defaulting; Hugs shows the type before, but
this can be changed with the +T option.


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