[GHC] #13742: Code using ConstraintKinds needs explicit kind signature with GHC 8.2.1

[GHC]

#13742: Code using ConstraintKinds needs explicit kind signature with GHC 8.2.1
-------------------------------------+-------------------------------------
        Reporter:  albertov          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  highest           |            Milestone:
       Component:  Compiler (Type    |              Version:  8.2.1-rc2
  checker)                           |             Keywords:
      Resolution:                    |  ConstraintKinds, KindSignatures
Operating System:  Unknown/Multiple  |         Architecture:
 Type of failure:  GHC rejects       |  Unknown/Multiple
  valid program                      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------
Description changed by RyanGlScott:

@@ -6,0 +6,29 @@
+
+ Compiling the attached file fails gives the error:
+
+ {{{
+ [[1 of 1] Compiling CKBug            ( CKBug.hs, interpreted )
+
+ CKBug.hs:33:4: error:
+     • Expected a type, but
+       ‘(PropagIOConstraint l a,
+         Missing (PropagIOVector l) (PropagIONullable l a),
+         Elem (PropagIONullable l a) ~ a)’ has kind
+       ‘Constraint’
+     • In the type ‘((PropagIOConstraint l a,
+                      Missing (PropagIOVector l) (PropagIONullable l a),
+                      Elem (PropagIONullable l a) ~ a))’
+       In the type declaration for ‘CanSerialize’
+    |
+ 33 |   (( PropagIOConstraint l a
+    |    ^^^^^^^^^^^^^^^^^^^^^^^^...
+
+ CKBug.hs:42:4: error:
+     • Expected a constraint,
+         but ‘(CanSerialize l Double, CanSerialize l Int)’ has kind ‘*’
+     • In the type ‘(CanSerialize l Double, CanSerialize l Int)’
+       In the type declaration for ‘CanSerializePropagTypes’
+    |
+ 42 |    ( CanSerialize l Double
+    |    ^^^^^^^^^^^^^^^^^^^^^^^...
+ }}}

New description:

 The attached module compiles without errors with GHC 8.0.1 but needs an
 explicit kind signature with GHC 8.2.1-rc2.

 Mentioned in this [https://mail.haskell.org/pipermail/ghc-
 devs/2017-May/014222.html ghc-dev thread].

 Compiling the attached file fails gives the error:

 {{{
 [[1 of 1] Compiling CKBug            ( CKBug.hs, interpreted )

 CKBug.hs:33:4: error:
     • Expected a type, but
       ‘(PropagIOConstraint l a,
         Missing (PropagIOVector l) (PropagIONullable l a),
         Elem (PropagIONullable l a) ~ a)’ has kind
       ‘Constraint’
     • In the type ‘((PropagIOConstraint l a,
                      Missing (PropagIOVector l) (PropagIONullable l a),
                      Elem (PropagIONullable l a) ~ a))’
       In the type declaration for ‘CanSerialize’
    |
 33 |   (( PropagIOConstraint l a
    |    ^^^^^^^^^^^^^^^^^^^^^^^^...

 CKBug.hs:42:4: error:
     • Expected a constraint,
         but ‘(CanSerialize l Double, CanSerialize l Int)’ has kind ‘*’
     • In the type ‘(CanSerialize l Double, CanSerialize l Int)’
       In the type declaration for ‘CanSerializePropagTypes’
    |
 42 |    ( CanSerialize l Double
    |    ^^^^^^^^^^^^^^^^^^^^^^^...
 }}}

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Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/13742#comment:2>
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