Re: [Haskell-cafe] do we have something like isDefined or isNull in Haskell?

On 6/15/06, Vladimir Portnykh wrote:

Suppose there is a data definition in Haskell: data MyType = MyType { date :: Double, weight :: Double, height :: Double } deriving (Eq, Ord, Show)

Is it possible to check if the field height, for example, is filled in(defined)? Can we give default values in Haskell?

Many thanks and sorry fro so sily questions. Vladimir

You could make date, weight, and height "Maybe Double"s, then isDefined = isJust and isNull = isNothing. Bryan