GitHub - dmjio/envy: :angry: Environmentally friendly environment variables

import System.Environment import Data.Text (pack) import Text.Read (readMaybe) data ConnectInfo = ConnectInfo { pgPort :: Int pgURL :: Text } deriving (Show, Eq) getPGPort :: IO ConnectInfo getPGPort = do portResult <- lookupEnv "PG_PORT" urlResult <- lookupEnv "PG_URL" case (portResult, urlResult) of (Just port, Just url) -> case readMaybe port :: Maybe Int of Nothing -> error "PG_PORT isn't a nu

[igrep]

“What if we could apply aeson's FromJSON / ToJSON pattern to give us variable lookups that provide both key-lookup and parse failure information?”