[GHC] #1127: Make StateT in mtl truly lazy

[GHC]

#1127: Make StateT in mtl truly lazy
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    Reporter:  igloo              |       Owner:         
        Type:  proposal           |      Status:  new    
    Priority:  normal             |   Milestone:  Not GHC
   Component:  libraries (other)  |     Version:  6.6    
    Severity:  normal             |    Keywords:         
  Difficulty:  Unknown            |    Testcase:         
Architecture:  Unknown            |          Os:  Unknown
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The StateT monad gives every impression of intending to be lazy, but the
 absence of a ~ means that it isn't fully lazy. This bit me in the
 compression library, meaning I currently bundle a LazyStateT module that
 provides essentially StateT with this change. There was also a recent
 discussion about it on one of the mailing lists:
 http://www.haskell.org/pipermail/haskell-cafe/2007-January/021244.html

 I propose making StateT lazy.

 Deadline: 28 February 2007.

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Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1127>
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