yesodweb/persistent

derivePersistField phantom type support

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#1 137 ouverte le 23 oct. 2020

 (8 commentaires) (0 réaction) (1 personne assignée)Haskell (302 forks)auto 404
Feature Requestgood first issue

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Description

Phantom types are very useful for tagging things on type level, but at the moment this code will not compile

-- @Employment.hs
{-# LANGUAGE TemplateHaskell #-}
module Employment where

import Database.Persist.TH
import Prelude

data Employment a = Employed | Unemployed | Retired
    deriving (Show, Read, Eq)
derivePersistField "Employment a"

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