package06e.hs:2:1: error:
    Could not find module ‘HsTypes’
    It is a member of the hidden package ‘ghc-8.1’.
    Use -v to see a list of the files searched for.

package06e.hs:3:1: error:
    Could not find module ‘UniqFM’
    It is a member of the hidden package ‘ghc-8.1’.
    Use -v to see a list of the files searched for.