rnfail052.hs:7:6: error:
    Illegal symbol ‘forall’ in type
    Suggested fix:
      Perhaps you intended to use RankNTypes
      or a similar language extension to enable explicit-forall syntax: forall <tvs>. <type>

rnfail052.hs:10:14: error:
    Illegal symbol ‘forall’ in type
    Suggested fix:
      Perhaps you intended to use RankNTypes
      or a similar language extension to enable explicit-forall syntax: forall <tvs>. <type>

rnfail052.hs:13:15: error:
    Illegal symbol ‘forall’ in type
    Suggested fix:
      Perhaps you intended to use RankNTypes
      or a similar language extension to enable explicit-forall syntax: forall <tvs>. <type>