ghci: catching up with hugs?-)

Serge D. Mechveliani mechvel at botik.ru
Fri Jul 30 00:20:18 EDT 2004


I also would like to have the info on clases and instances in the
:info  interactive command.

-----------------
Serge Mechveliani
mechvel at botik.ru


On Thu, Jul 29, 2004 at 05:48:26PM +0100, Claus Reinke wrote:

> [..]
> 
>     in hugs, a simple ":info <type>" gives me the answer:
> 
>         Prelude> :info Bool
>         -- type constructor
>         data Bool
>         
>         -- constructors:
>         False :: Bool
>         True :: Bool
>         
>         -- instances:
>         instance Eq Bool
>         instance Ord Bool
>         instance Ix Bool
>         instance Enum Bool
>         instance Read Bool
>         instance Show Bool
>         instance Bounded Bool
> 
>     in fact, I can even ask by class, using ":info <class>":
> 
>         Prelude> :i Enum
>         -- type class
>         class Enum a where
>           succ :: a -> a
>           pred :: a -> a
>           toEnum :: Int -> a
>           fromEnum :: a -> Int
>           enumFrom :: a -> [a]
>           enumFromThen :: a -> a -> [a]
>           enumFromTo :: a -> a -> [a]
>           enumFromThenTo :: a -> a -> a -> [a]
>         
>         -- instances:
>         instance Enum ()
>         instance Enum Char
>         instance Enum Int
>         instance Enum Integer
>         instance Enum Float
>         instance Enum Double
>         instance Integral a => Enum (Ratio a)
>         instance Enum Bool
>         instance Enum Ordering
> 
> [..]


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