Is there a better way to express this type?
I've made this data type, which has a lot of repetition in it.
data JobState = UnsanitizedData Handle
| SanitizedData Handle
| VerifiedData Handle
| JobFail Handle
I don't want a开发者_如何学运维ny of these JobStates to ever be used without Handle. But the repetition has me suspecting I'm not expressing this correctly. Is there a better way?
One way would be to factor this out into a state value, and a wrapper that includes the handle:
data JobState = UnsanitizedData | SanitizedData | VerifiedData | JobFail
deriving (Eq, Enum, Ord, Show, Read)
data Job = Job { jobState :: JobState, jobHandle :: Handle }
-- or: data Job = Job JobState Handle
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