overlapping instances in 7.10.1

Sergei Meshveliani mechvel at botik.ru
Sat May 23 21:08:02 UTC 2015

Dear GHC developers, 

This request overrides my previous one of  "7.10.1-err..."
(it is simpler and more precise).
The archive


presents a question about  ghc-7.10.1.
Make it, please, with  ghc-7.10.1  by   

         ghc $doconCpOpt -O --make Main
$doconCpOpt = 
 -fwarn-unused-matches -fwarn-unused-binds -fwarn-unused-imports 
 -fno-warn-overlapping-patterns -XRecordWildCards -XNamedFieldPuns 
 -XFlexibleContexts -XMultiParamTypeClasses -XUndecidableInstances
 -XTypeSynonymInstances -XFlexibleInstances -fcontext-stack=30

as it is written there in  README.txt.

README.txt  explains which two instances are wrongly resolved
-- as I expect.

In  ghc-7.8.2  they are resolved in a correct way
(and there is a different pragma syntax).
I conclude this from running the test in  docon-2.12.

Am I missing something?

Please, advise,


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