__   __ __  __  ____   ___      _________________________________________
||   || ||  || ||  || ||__      Hugs 98: Based on the Haskell 98 standard
||___|| ||__|| ||__||  __||     Copyright (c) 1994-2005
||---||         ___||           World Wide Web: http://haskell.org/hugs
||   ||                         Report bugs to: hugs-bugs@haskell.org
||   || Version: March 2005     _________________________________________

Hugs mode: Restart with command line option +98 for Haskell 98 mode

Type :? for help
PrecExpr> Just "(((a+b)+c)+d)"
PrecExpr> Just "((a+(b*c))+d)"
PrecExpr> Just "(a+((b*c)*d))"
PrecExpr> Just "(((a+b)+(-c))+d)"
PrecExpr> Just "((a+((-b)*c))+d)"
PrecExpr> [Leaving Hugs]