[GHC] #4370: Bring back monad comprehensions

[GHC]

#4370: Bring back monad comprehensions
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  Reporter:  simonpj          |          Owner:  nsch            
      Type:  feature request  |         Status:  closed          
  Priority:  normal           |      Milestone:  7.4.1           
 Component:  Compiler         |        Version:  6.12.3          
Resolution:  fixed            |       Keywords:                  
  Testcase:                   |      Blockedby:                  
Difficulty:                   |             Os:  Unknown/Multiple
  Blocking:                   |   Architecture:  Unknown/Multiple
   Failure:  None/Unknown     |  
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Comment(by simonpj):

 I intended it.  It seems reasonable that
  * `-XMonadComprehensions` makes list comprehensions be interpreted as
 monad comprehensions
  * `-XTransformListComp` adds the SQL-like comprehension support, to
 either list or monad comprehensions
  * Ditto for `-XParallelListComp`

 Admittedly `TransformListComp` then is not necessarily about '''list'''
 comprehensions.  Maybe is should be `TransformComp`; and similarly for
 `ParallelComp`?

 That woudl be doable; we'd have to go through a cycle of deprecation to
 encourage people to adopt the new flag name.

 Does the logic make sense though?

 Simon

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/4370#comment:59>
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