Remove fun_infix from Funbind, as it is now in Match

One of the changes D538 introduced is to add `m_fun_id_infix` to `Match`

```lang=hs
data Match id body
  = Match {
        m_fun_id_infix :: (Maybe (Located id,Bool)),
          -- fun_id and fun_infix for functions with multiple equations
          -- only present for a RdrName. See note [fun_id in Match]
        m_pats :: [LPat id], -- The patterns
        m_type :: (Maybe (LHsType id)),
                                 -- A type signature for the result of the match
                                 -- Nothing after typechecking
        m_grhss :: (GRHSs id body)
  } deriving (Typeable)
```

This was done to track the individual locations and fixity of the
`fun_id` for each of the defining equations for a function when there
are more than one.

For example, the function `(&&&)` is defined with some prefix and some
infix equations below.

```lang=hs
    (&&&  ) [] [] =  []
    xs    &&&   [] =  xs
    (  &&&  ) [] ys =  ys
```

This means that the fun_infix is now superfluous in the `FunBind`. This
has not been removed as a potentially risky change just before 7.10 RC2,
and so must be done after.

This ticket captures that task, which includes processing these fields
through the renamer and beyond.

Ticket #9988 introduced these fields into `Match` through renaming, this
ticket it to continue through type checking and then remove it from
`FunBind` completely.

The split happened so that #9988 could land in 7.10

Trac ticket : #10061

Test Plan: ./validate

Reviewers: goldfire, austin, simonpj, bgamari

Reviewed By: bgamari

Subscribers: simonpj, thomie, mpickering

Differential Revision: https://phabricator.haskell.org/D1285

GHC Trac Issues: #10061

1 files changed, 2 insertions, 2 deletions

diff --git a/compiler/deSugar/Match.hs b/compiler/deSugar/Match.hs
index 5840578942..8af0a6e5e3 100644
--- a/compiler/deSugar/Match.hs
+++ b/compiler/deSugar/Match.hs
@@ -148,8 +148,8 @@ pp_context (DsMatchContext kind _loc) msg rest_of_msg_fun
   where
     (ppr_match, pref)
         = case kind of
-             FunRhs fun _ -> (pprMatchContext kind, \ pp -> ppr fun <+> pp)
-             _            -> (pprMatchContext kind, \ pp -> pp)
+             FunRhs fun -> (pprMatchContext kind, \ pp -> ppr fun <+> pp)
+             _          -> (pprMatchContext kind, \ pp -> pp)
 
 ppr_pats :: Outputable a => [a] -> SDoc
 ppr_pats pats = sep (map ppr pats)