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@ddellacosta
Last active December 31, 2019 02:06
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deriving newtype instance for UUID fails
module Fail where
import Data.UUID (UUID)
import Simple.JSON as JSON
newtype AnId = AnId UUID
derive newtype instance readAnId :: JSON.ReadForeign AnId
-- error:
Compiling Main
Error 1 of 2:
in module Fail
at src/Fail.purs:8:1 - 8:58 (line 8, column 1 - line 8, column 58)
No type class instance was found for
Simple.JSON.ReadForeign UUID
while checking that expression #dict ReadForeign
has type { readImpl :: Foreign -> ExceptT (NonEmptyList ForeignError) Identity AnId
}
in value declaration readAnId
See https://github.com/purescript/documentation/blob/master/errors/NoInstanceFound.md for more information,
or to contribute content related to this error.
-- other error is unrelated module
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