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brendanhay / amazonka

A comprehensive Amazon Web Services SDK for Haskell.
https://amazonka.brendanhay.nz
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Generalise Service Error Matcher Optics #878

Closed endgame closed 1 year ago

endgame commented 1 year ago

The service error matchers have a type annotation which restricts them to AsError a => Getting (First ServiceError) a ServiceError. Generalise the type signature to the AsError a => Fold a ServiceError that they are, and update the generator to annotate generated matchers correctly also.

The optics actually type-check as AsError a => Traversal' a ServiceError or even AsError a => Prism' a ServiceError, but because they use filtered internally, those optics are only lawful if data written back through them satisfies the predicate. Since their old type signature meant they were only usable for matching and nobody has complained, the ability to write back through them has probably not been missed.

This means we'll have to regenerate everything again, so update botocore and configure new services too. Note that this time existing code will continue to work, but I'll aim to get the regeneration up ASAP.

endgame commented 1 year ago

People have never been able to do silly things, but now they are able to do more not-silly things with an error matcher than just preview through it. has is the obvious one.