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<p class="MsoNormal">If ‘transformers’ purposely has orphan instances, shouldn’t we switch off the warnings about them?<o:p></o:p></p>
<p class="MsoNormal">Simon<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="Code">"/opt/ghc/bin/ghc" -hisuf hi -osuf o -hcsuf hc -static -O -H64m -Wall -package-db libraries/bootstrapping.conf -this-unit-id transformers-0.5.6.2 -hide-all-packages -package-env - -i -ilibraries/transformers/. -ilibraries/transformers/dist-boot/build
-Ilibraries/transformers/dist-boot/build -ilibraries/transformers/dist-boot/build/./autogen -Ilibraries/transformers/dist-boot/build/./autogen -Ilibraries/transformers/. -optP-include -optPlibraries/transformers/dist-boot/build/./autogen/cabal_macros.h
-package-id base-4.14.1.0 -XHaskell98 -no-user-package-db -rtsopts -fno-warn-unused-matches -fno-warn-unused-imports -fno-warn-deprecated-flags -outputdir libraries/transformers/dist-boot/build -c libraries/transformers/./Control/Applicative/Lift.hs
-o libraries/transformers/dist-boot/build/Control/Applicative/Lift.o <o:p></o:p></p>
<p class="Code"><o:p> </o:p></p>
<p class="Code">libraries/transformers/Control/Monad/Trans/Error.hs:98:1: warning: [-Worphans]<o:p></o:p></p>
<p class="Code"> Orphan instance: instance [safe] Error e => Alternative (Either e)<o:p></o:p></p>
<p class="Code"> To avoid this<o:p></o:p></p>
<p class="Code"> move the instance declaration to the module of the class or of the type, or<o:p></o:p></p>
<p class="Code"> wrap the type with a newtype and declare the instance on the new type.<o:p></o:p></p>
<p class="Code"> |<o:p></o:p></p>
<p class="Code">98 | instance (Error e) => Alternative (Either e) where<o:p></o:p></p>
<p class="Code"> | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...<o:p></o:p></p>
<p class="Code"><o:p> </o:p></p>
<p class="Code">libraries/transformers/Control/Monad/Trans/Error.hs:103:1: warning: [-Worphans]<o:p></o:p></p>
<p class="Code"> Orphan instance: instance [safe] Error e => MonadPlus (Either e)<o:p></o:p></p>
<p class="Code"> To avoid this<o:p></o:p></p>
<p class="Code"> move the instance declaration to the module of the class or of the type, or<o:p></o:p></p>
<p class="Code"> wrap the type with a newtype and declare the instance on the new type.<o:p></o:p></p>
<p class="Code"> |<o:p></o:p></p>
<p class="Code">103 | instance (Error e) => MonadPlus (Either e) where<o:p></o:p></p>
<p class="Code"> | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^... <span style="font-size:11.0pt;font-family:"Calibri",sans-serif">
<o:p></o:p></span></p>
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