Simplify OutputableBndr

This replaces three methods in OutputableBndr with one,
and adds comments.

There's also a tiny change in the placement of equals signs in
debug-prints.  I like it better that way, but if it complicates
life for anyone we can put it back.

1 files changed, 6 insertions, 12 deletions

diff --git a/compiler/utils/Outputable.hs b/compiler/utils/Outputable.hs
index d78411a893..8a2afbec79 100644
--- a/compiler/utils/Outputable.hs
+++ b/compiler/utils/Outputable.hs
@@ -962,18 +962,12 @@ class Outputable a => OutputableBndr a where
       -- prefix position of an application, thus   (f a b) or  ((+) x)
       -- or infix position,                 thus   (a `f` b) or  (x + y)
 
-   pprNonRecBndrKeyword, pprRecBndrKeyword :: a -> SDoc
-      -- Print which keyword introduces the binder in Core code. This should be
-      -- "let" or "letrec" for a value but "join" or "joinrec" for a join point.
-   pprNonRecBndrKeyword _ = text "let"
-   pprRecBndrKeyword    _ = text "letrec"
-
-   pprLamsOnLhs :: a -> Int
-      -- For a join point of join arity n, we want to print j = \x1 ... xn -> e
-      -- as "j x1 ... xn = e" to differentiate when a join point returns a
-      -- lambda (the first rendering looks like a nullary join point returning
-      -- an n-argument function).
-   pprLamsOnLhs _ = 0
+   bndrIsJoin_maybe :: a -> Maybe Int
+   bndrIsJoin_maybe _ = Nothing
+      -- When pretty-printing we sometimes want to find
+      -- whether the binder is a join point.  You might think
+      -- we could have a function of type (a->Var), but Var
+      -- isn't available yet, alas
 
 {-
 ************************************************************************