[commit: ghc] master: Wibble to implicit-parameter error message (8c9d0ce)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/8c9d0ce490506fdc60d9f25d4b80774180cf92ce/ghc

>---------------------------------------------------------------

commit 8c9d0ce490506fdc60d9f25d4b80774180cf92ce
Author: Simon Peyton Jones <simonpj at microsoft.com>
Date:   Fri Sep 26 10:48:25 2014 +0100

    Wibble to implicit-parameter error message


>---------------------------------------------------------------

8c9d0ce490506fdc60d9f25d4b80774180cf92ce
 compiler/typecheck/TcRnTypes.lhs                   |  2 +-
 testsuite/tests/typecheck/should_fail/T5246.stderr | 10 ++++++----
 testsuite/tests/typecheck/should_fail/T7525.stderr |  2 +-
 3 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/compiler/typecheck/TcRnTypes.lhs b/compiler/typecheck/TcRnTypes.lhs
index bff59ee..1be81cb 100644
--- a/compiler/typecheck/TcRnTypes.lhs
+++ b/compiler/typecheck/TcRnTypes.lhs
@@ -1734,7 +1734,7 @@ pprSkolInfo (SigSkol (FunSigCtxt f) ty)
                                  2 (pprPrefixOcc f <+> dcolon <+> ppr ty)
 pprSkolInfo (SigSkol cx ty) = hang (pprUserTypeCtxt cx <> colon)
                                  2 (ppr ty)
-pprSkolInfo (IPSkol ips)    = ptext (sLit "the implicit-parameter bindings for")
+pprSkolInfo (IPSkol ips)    = ptext (sLit "the implicit-parameter binding") <> plural ips <+> ptext (sLit "for")
                               <+> pprWithCommas ppr ips
 pprSkolInfo (ClsSkol cls)   = ptext (sLit "the class declaration for") <+> quotes (ppr cls)
 pprSkolInfo InstSkol        = ptext (sLit "the instance declaration")
diff --git a/testsuite/tests/typecheck/should_fail/T5246.stderr b/testsuite/tests/typecheck/should_fail/T5246.stderr
index bd075cb..454c2b7 100644
--- a/testsuite/tests/typecheck/should_fail/T5246.stderr
+++ b/testsuite/tests/typecheck/should_fail/T5246.stderr
@@ -1,9 +1,11 @@
 
 T5246.hs:11:10:
-    Could not deduce (?x::Int) arising from a use of ‘foo’
-    from the context (?x::[Char])
-      bound by the implicit-parameter bindings for ?x
-      at T5246.hs:(10,7)-(11,12)
+    Couldn't match type ‘[Char]’ with ‘Int’
+    arising from a functional dependency between constraints:
+      ‘?x::Int’ arising from a use of ‘foo’ at T5246.hs:11:10-12
+      ‘?x::[Char]’
+        arising from the implicit-parameter binding for ?x
+        at T5246.hs:(10,7)-(11,12)
     In the expression: foo
     In the expression: let ?x = "hello" in foo
     In an equation for ‘bar’: bar = let ?x = "hello" in foo
diff --git a/testsuite/tests/typecheck/should_fail/T7525.stderr b/testsuite/tests/typecheck/should_fail/T7525.stderr
index 9524d1a..ecf3eb1 100644
--- a/testsuite/tests/typecheck/should_fail/T7525.stderr
+++ b/testsuite/tests/typecheck/should_fail/T7525.stderr
@@ -3,7 +3,7 @@ T7525.hs:5:30:
     Could not deduce (?b::Bool)
       arising from a use of implicit parameter ‘?b’
     from the context (?a::Bool)
-      bound by the implicit-parameter bindings for ?a at T7525.hs:5:7-31
+      bound by the implicit-parameter binding for ?a at T7525.hs:5:7-31
     In the second argument of ‘(&&)’, namely ‘?b’
     In the expression: ?a && ?b
     In the expression: let ?a = True in ?a && ?b