[project @ 2001-10-25 02:13:10 by sof]

- Pet peeve removal / code tidyup, replaced various sub-optimal
  uses of 'length' with something a bit better, i.e., replaced
  the following patterns

   *  length as `cmpOp` length bs
   *  length as `cmpOp` val   -- incl. uses where val == 1 and val == 0
   *  {take,drop,splitAt} (length as) bs
   *  length [ () | pat <- as ]

  with uses of misc Util functions.

  I'd be surprised if there's a noticeable reduction in running
  times as a result of these changes, but every little bit helps.

  [ The changes have been tested wrt testsuite/ - I'm seeing a couple
    of unexpected breakages coming from CorePrep, but I'm currently
    assuming that these are due to other recent changes. ]

- compMan/CompManager.lhs: restored 4.08 compilability + some code
  cleanup.

None of these changes are HEADworthy.

1 files changed, 2 insertions, 1 deletions

diff --git a/ghc/compiler/deSugar/DsUtils.lhs b/ghc/compiler/deSugar/DsUtils.lhs
index 008cebf6bf..b83b78429f 100644
--- a/ghc/compiler/deSugar/DsUtils.lhs
+++ b/ghc/compiler/deSugar/DsUtils.lhs
@@ -63,6 +63,7 @@ import PrelNames	( unpackCStringName, unpackCStringUtf8Name,
 			  plusIntegerName, timesIntegerName )
 import Outputable
 import UnicodeUtil      ( stringToUtf8 )
+import Util             ( isSingleton )
 \end{code}
 
 
@@ -430,7 +431,7 @@ mkSelectorBinds (VarPat v) val_expr
   = returnDs [(v, val_expr)]
 
 mkSelectorBinds pat val_expr
-  | length binders == 1 || is_simple_pat pat
+  | isSingleton binders || is_simple_pat pat
   = newSysLocalDs (exprType val_expr)	`thenDs` \ val_var ->
 
 	-- For the error message we don't use mkErrorAppDs to avoid