[Haskell-cafe] AbstractDataType question

Jason Bailey azrael at demonlords.net
Sun Dec 12 13:08:30 EST 2004

So in the wiki on AbstractDataType ( 
http://haskell.org/hawiki/AbstractDataType )

it gives the following example:

data Tree a = Nil  
            | Node { left  :: Tree a,
                     value :: a,
                     right :: Tree a }

The part where I am confused is with the use of '{' and '}' my reference 
book is apparently out of date as it states that Haskell doesn't even 
use those characters :)

Could someone point me to some documentation on whats being created here 
and how its used?

thank you

More information about the Haskell-Cafe mailing list