[project @ 2002-06-18 13:58:22 by simonpj]

---------------------------------------
	    Rehash the handling of SeqOp
	---------------------------------------

See the comments in the commentary (Cunning Prelude Code).

* Expunge SeqOp altogether

* Add GHC.Base.lazy :: a -> a
  to GHC.Base

* Add GHC.Base.lazy
  to basicTypes/MkId.  The idea is that this defn will over-ride
  the info from GHC.Base.hi, thereby hiding strictness and
  unfolding

* Make stranal/WorkWrap do a "manual inlining" for GHC.Base.lazy
  This happens nicely after the strictness analyser has run.

* Expunge the SeqOp/ParOp magic in CorePrep

* Expunge the RULE for seq in PrelRules

* Change the defns of pseq/par in GHC.Conc to:

	{-# INLINE pseq  #-}
       	pseq :: a -> b -> b
       	pseq  x y = x `seq` lazy y

       	{-# INLINE par  #-}
       	par :: a -> b -> b
       	par  x y = case (par# x) of { _ -> lazy y }

1 files changed, 8 insertions, 0 deletions

diff --git a/libraries/base/GHC/Base.lhs b/libraries/base/GHC/Base.lhs
index 45138d2c19..8abd593b99 100644
--- a/libraries/base/GHC/Base.lhs
+++ b/libraries/base/GHC/Base.lhs
@@ -564,6 +564,14 @@ compareInt# x# y#
 id			:: a -> a
 id x			=  x
 
+-- lazy function; this is just the same as id, but its unfolding
+-- and strictness are over-ridden by the definition in MkId.lhs
+-- That way, it does not get inlined, and the strictness analyser
+-- sees it as lazy.  Then the worker/wrapper phase inlines it.
+-- Result: happiness
+lazy :: a -> a
+lazy x = x
+
 -- constant function
 const			:: a -> b -> a
 const x _		=  x