On Sun Apr 30 19:35:17 UTC 2017 Brandon Allbery wrote:

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On Sun, Apr 30, 2017 at 3:31 PM, Richard Eisenberg wrote:

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On Apr 30, 2017, at 6:37 AM, Anthony Clayden wrote: Is that behaviour officially documented somewhere?

Not that I can find. ...

... the originally cited behavior of equality constraints could also stand to be documented. ..

Thanks Brandon, I've added a request to #10431 [q.v.]. Actually, the required flags are documented, just in an obscure place. Anyway it's not too bad: GHC's error message tells you what to do. AntC