[GHC] #3380: [Patch] Support implicit concatenation in list comprehensions

[GHC]

#3380: [Patch] Support implicit concatenation in list comprehensions
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 Reporter:  batterseapower    |          Owner:                  
     Type:  feature request   |         Status:  new             
 Priority:  normal            |      Milestone:                  
Component:  Compiler          |        Version:  6.10.4          
 Severity:  normal            |     Resolution:                  
 Keywords:                    |       Testcase:                  
       Os:  Unknown/Multiple  |   Architecture:  Unknown/Multiple
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Comment (by batterseapower):

 NB: this generalises to instances of MonadPlus, but I can't think of a
 nice-looking syntax.

 {{{
 [e1, e2 | qs]
 = concat [[e1, e2] | qs]
 = join [return e1 `mplus` return e2 | qs]
 }}}

 This is pretty easy to implement as long as you can come up with the
 syntax.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/3380#comment:2>
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