On Fri, Aug 14, 2015 at 2:53 PM, Dimitri DeFigueiredo <defigueiredo@ucdavis.edu> wrote:
executable a
  main-is:          MainA.hs
  hs-source-dirs:   ./src

Looks to me like you have told it that MinhaCommon is an executable with no library component. Installing it therefore created and installed a program named "a", without registering a library.

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