[Haskell-beginners] Type constructor

[mike h]

Duh!   
Give that man a ceeeegar! 
Thanks
:)

> On 8 Nov 2017, at 19:31, David McBride <toad3k at gmail.com> wrote:
> 
> The only thing I can think of is that you wrote a Num instance for Fraction.  That allows it to represent a fraction as a literal 2 because you can create a fraction from an integer via fromInteger.
> 
> On Wed, Nov 8, 2017 at 2:21 PM, mike h <mike_k_houghton at yahoo.co.uk <mailto:mike_k_houghton at yahoo.co.uk>> wrote:
> Hi,
> 
> I’m modelling fractions with a view to looking at continued fractions and I have this recursive structure.
> 
> type Numerator   = Integer
> data Fraction = Numbr Integer | F Numerator Fraction
> 
> 
> in ghci I do
> 
> λ-> :t F 1 (Numbr 2)
> F 1 (Numbr 2) :: Fraction
> 
> which is fine. But what surprised me is that it also works without using Numbr e.g.
> 
> λ-> :t F 1 2
> F 1 2 :: Fraction
> 
> why is this?
> 
> Thanks
> 
> Mike
> _______________________________________________
> Beginners mailing list
> Beginners at haskell.org <mailto:Beginners at haskell.org>
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners <http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners>
> 
> _______________________________________________
> Beginners mailing list
> Beginners at haskell.org
> http://mail.haskell.org/cgi-bin/mailman/listinfo/beginners

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/beginners/attachments/20171108/23d431a7/attachment.html>