[Haskell-beginners] print 
dav.vire+haskell at gmail.com
Wed Aug 14 12:08:39 CEST 2013
2013/8/13 Lukas Lehner <lehner.lukas at gmail.com>:
> Good to know extension. And without it?
Someone correct me if I'm wrong, here's how I understand it:
To execute print , ghc has to find which instance of Show to call.
How could it find an instance without knowing the type ?
 could be a list of anything, and while in theory we know that in
all cases it should print "", in practice ghc can't call that code
if it doesn't know the type of the list.
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