haskell-graphql / graphql-api

Write type-safe GraphQL services in Haskell
BSD 3-Clause "New" or "Revised" License
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Format error typeclass #72

Closed jml closed 7 years ago

jml commented 7 years ago

As mentioned in #66.

Lots of human-readable errors.

I haven't actually verified any of them, but I reckon this is an improvement, and should signal clearly to our users that we care about this sort of thing.

Changed the union handling a bit because I couldn't understand the error conditions well enough. See commit message on c0e0f67 for rationale.