Improve error message for Typeable k (T k)

GHC can't yest build a TypeRep for a type involving kind variables.
(We await kinds = types for that.)  But the error message was terrible,
as fixing #10524 reminded me.

This improves it a lot.

1 files changed, 10 insertions, 12 deletions

diff --git a/testsuite/tests/annotations/should_fail/annfail08.stderr b/testsuite/tests/annotations/should_fail/annfail08.stderr
index 2a9980dcb6..66e9c7e29b 100644
--- a/testsuite/tests/annotations/should_fail/annfail08.stderr
+++ b/testsuite/tests/annotations/should_fail/annfail08.stderr
@@ -1,12 +1,10 @@
-

-annfail08.hs:9:1:

-    No instance for (Data (a0 -> a0))

-      (maybe you haven't applied a function to enough arguments?)

-      arising from an annotation

-    In the annotation: {-# ANN f (id + 1) #-}

-

-annfail08.hs:9:15:

-    No instance for (Num (a0 -> a0))

-      (maybe you haven't applied a function to enough arguments?)

-      arising from a use of ‘+’

-    In the annotation: {-# ANN f (id + 1) #-}

+
+annfail08.hs:9:1: error:
+    No instance for (Data (a0 -> a0)) arising from an annotation
+      (maybe you haven't applied a function to enough arguments?)
+    In the annotation: {-# ANN f (id + 1) #-}
+
+annfail08.hs:9:15: error:
+    No instance for (Num (a0 -> a0)) arising from a use of ‘+’
+      (maybe you haven't applied a function to enough arguments?)
+    In the annotation: {-# ANN f (id + 1) #-}