Generator of "valid" and "invalid" data in a type class
For example, if you created
data Person = Anonymous { getId::String } | Client { getUsername::String, getName::String, getEmail::String} deriving(Show,Eq)We can provide means to generate valid and invalid data, like:
instance Variant Person where
valid = do
id <- alternative
username <- alternative
name <- alternative
domain <- alternative
ext <- alternative
(oneof . return) [Anonymous id, Client username name (username++"@"++domain++ext)]
invalid = do
username <- alternative
name <- alternative
return $ Client username name ""
See this post for more details
