Re: [Haskell-cafe] default values in a record structure

On Tue, Apr 28, 2009 at 4:09 PM, Vasili I. Galchin wrote:

Hello,

Is there anyway when defining a dat type record struct to indicate default values for some of the

fields? The usual pattern is to use a default record, and specialize it: data Foo = Foo { bar :: Int, baz :: Int, quux :: Int } fooDefault = Foo { bar = 1, baz = 2, quux = 3 } newRecord = fooDefault { quux = 42 } If you only want some of the fields to be defaulted, you can make them undefined in the default record... unfortunately this won't be checked by the compiler. Luke