mod143.hs:2:21: error: [GHC-69158]
    Conflicting exports for ‘Foo’:
       ‘module Mod143_A’ exports ‘Mod143_A.Foo’
         imported from ‘Mod143_A’ at mod143.hs:4:1-15
         (and originally defined at Mod143_A.hs:3:1-14)
       ‘module M’ exports ‘M.Foo’ defined at mod143.hs:6:1