[Haskell-beginners] small expression evaluator

Henk-Jan van Tuyl hjgtuyl at chello.nl
Tue Mar 22 10:14:57 CET 2011


On Tue, 22 Mar 2011 08:56:45 +0100, Petr Novotnik  
<pnovotnik at googlemail.com> wrote:

> data Person = Person {
>        personName :: String
>      , personAge :: Int
>      }
>      deriving (Show)
>
> exampleExpr :: Bool
> exampleExpr = (VConst 99) .==. (VFunc personAge) $ Person "pete" 99
>
>
> I was wondering, whether it'd be possible to enable defining expression  
> without the Value data constructors, i.e.
>
>
>     99 .==. personAge $ Person "pete" 99

You can write:
   99 == personAge (Person "pete" 99)

Regards,
Henk-Jan van Tuyl


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